make sure typevars defined in stubs are private (#989)

And also a few type aliases I noticed in the process.

Found using 59f9cac095

stdlib/2/__builtin__.pyi

@@ -815,12 +815,12 @@ class ellipsis: ...
 Ellipsis = ...  # type: ellipsis
 
 # TODO: buffer support is incomplete; e.g. some_string.startswith(some_buffer) doesn't type check.
-AnyBuffer = TypeVar('AnyBuffer', str, unicode, bytearray, buffer)
+_AnyBuffer = TypeVar('_AnyBuffer', str, unicode, bytearray, buffer)
 
 class buffer(Sized):
-    def __init__(self, object: AnyBuffer, offset: int = ..., size: int = ...) -> None: ...
-    def __add__(self, other: AnyBuffer) -> str: ...
-    def __cmp__(self, other: AnyBuffer) -> bool: ...
+    def __init__(self, object: _AnyBuffer, offset: int = ..., size: int = ...) -> None: ...
+    def __add__(self, other: _AnyBuffer) -> str: ...
+    def __cmp__(self, other: _AnyBuffer) -> bool: ...
     def __getitem__(self, key: Union[int, slice]) -> str: ...
     def __getslice__(self, i: int, j: int) -> str: ...
     def __len__(self) -> int: ...

stdlib/2/array.pyi

@@ -3,13 +3,13 @@
 from typing import (Any, Generic, IO, Iterable, Sequence, TypeVar,
                     Union, overload, Iterator, Tuple, BinaryIO, List)
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
-class array(Generic[T]):
-    def __init__(self, typecode: str, init: Iterable[T] = ...) -> None: ...
-    def __add__(self, y: "array[T]") -> "array[T]": ...
+class array(Generic[_T]):
+    def __init__(self, typecode: str, init: Iterable[_T] = ...) -> None: ...
+    def __add__(self, y: "array[_T]") -> "array[_T]": ...
     def __contains__(self, y: Any) -> bool: ...
-    def __copy__(self) -> "array[T]": ...
+    def __copy__(self) -> "array[_T]": ...
     def __deepcopy__(self) -> "array": ...
     def __delitem__(self, y: Union[slice, int]) -> None: ...
     def __delslice__(self, i: int, j: int) -> None: ...
@@ -17,39 +17,39 @@ class array(Generic[T]):
     def __getitem__(self, i: int) -> Any: ...
     @overload
     def __getitem__(self, s: slice) -> "array": ...
-    def __iadd__(self, y: "array[T]") -> "array[T]": ...
-    def __imul__(self, y: int) -> "array[T]": ...
-    def __iter__(self) -> Iterator[T]: ...
+    def __iadd__(self, y: "array[_T]") -> "array[_T]": ...
+    def __imul__(self, y: int) -> "array[_T]": ...
+    def __iter__(self) -> Iterator[_T]: ...
     def __len__(self) -> int: ...
-    def __mul__(self, n: int) -> "array[T]": ...
-    def __rmul__(self, n: int) -> "array[T]": ...
+    def __mul__(self, n: int) -> "array[_T]": ...
+    def __rmul__(self, n: int) -> "array[_T]": ...
     @overload
-    def __setitem__(self, i: int, y: T) -> None: ...
+    def __setitem__(self, i: int, y: _T) -> None: ...
     @overload
-    def __setitem__(self, i: slice, y: "array[T]") -> None: ...
+    def __setitem__(self, i: slice, y: "array[_T]") -> None: ...
 
-    def append(self, x: T) -> None: ...
+    def append(self, x: _T) -> None: ...
     def buffer_info(self) -> Tuple[int, int]: ...
     def byteswap(self) -> None:
         raise RuntimeError()
     def count(self) -> int: ...
-    def extend(self, x: Sequence[T]) -> None: ...
-    def fromlist(self, list: List[T]) -> None:
+    def extend(self, x: Sequence[_T]) -> None: ...
+    def fromlist(self, list: List[_T]) -> None:
         raise EOFError()
         raise IOError()
     def fromfile(self, f: BinaryIO, n: int) -> None: ...
     def fromstring(self, s: str) -> None: ...
     def fromunicode(self, u: unicode) -> None: ...
-    def index(self, x: T) -> int: ...
-    def insert(self, i: int, x: T) -> None: ...
-    def pop(self, i: int = ...) -> T: ...
+    def index(self, x: _T) -> int: ...
+    def insert(self, i: int, x: _T) -> None: ...
+    def pop(self, i: int = ...) -> _T: ...
     def read(self, f: IO[str], n: int) -> None:
         raise DeprecationWarning()
-    def remove(self, x: T) -> None: ...
+    def remove(self, x: _T) -> None: ...
     def reverse(self) -> None: ...
     def tofile(self, f: BinaryIO) -> None:
         raise IOError()
-    def tolist(self) -> List[T]: ...
+    def tolist(self) -> List[_T]: ...
     def tostring(self) -> str: ...
     def tounicode(self) -> unicode: ...
     def write(self, f: IO[str]) -> None:

stdlib/2and3/_bisect.pyi

@@ -2,10 +2,10 @@
 
 from typing import Any, Sequence, TypeVar
 
-T = TypeVar('T')
-def bisect(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> int: ...
-def bisect_left(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> int: ...
-def bisect_right(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> int: ...
-def insort(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> None: ...
-def insort_left(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> None: ...
-def insort_right(a: Sequence[T], x: T, lo: int = ..., hi: int = ...) -> None: ...
+_T = TypeVar('_T')
+def bisect(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> int: ...
+def bisect_left(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> int: ...
+def bisect_right(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> int: ...
+def insort(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> None: ...
+def insort_left(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> None: ...
+def insort_right(a: Sequence[_T], x: _T, lo: int = ..., hi: int = ...) -> None: ...

stdlib/3.4/asyncio/locks.pyi

@@ -4,7 +4,7 @@ from .coroutines import coroutine
 from .events import AbstractEventLoop
 from .futures import Future
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
 __all__ = ...  # type: str
 
@@ -44,7 +44,7 @@ class Condition(_ContextManagerMixin):
     @coroutine
     def wait(self) -> Generator[Any, None, bool]: ...
     @coroutine
-    def wait_for(self, predicate: Callable[[], T]) -> Generator[Any, None, T]: ...
+    def wait_for(self, predicate: Callable[[], _T]) -> Generator[Any, None, _T]: ...
     def notify(self, n: int = 1) -> None: ...
     def notify_all(self) -> None: ...
 

stdlib/3.4/asyncio/queues.pyi

@@ -10,13 +10,13 @@ __all__ = ...  # type: str
 class QueueEmpty(Exception): ...
 class QueueFull(Exception): ...
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
-class Queue(Generic[T]):
+class Queue(Generic[_T]):
     def __init__(self, maxsize: int = ..., *, loop: AbstractEventLoop = ...) -> None: ...
     def _init(self, maxsize: int) -> None: ...
-    def _get(self) -> T: ...
-    def _put(self, item: T) -> None: ...
+    def _get(self) -> _T: ...
+    def _put(self, item: _T) -> None: ...
     def __repr__(self) -> str: ...
     def __str__(self) -> str: ...
     def _format(self) -> str: ...
@@ -28,11 +28,11 @@ class Queue(Generic[T]):
     def empty(self) -> bool: ...
     def full(self) -> bool: ...
     @coroutine
-    def put(self, item: T) -> Generator[Any, None, None]: ...
-    def put_nowait(self, item: T) -> None: ...
+    def put(self, item: _T) -> Generator[Any, None, None]: ...
+    def put_nowait(self, item: _T) -> None: ...
     @coroutine
-    def get(self) -> Generator[Any, None, T]: ...
-    def get_nowait(self) -> T: ...
+    def get(self) -> Generator[Any, None, _T]: ...
+    def get_nowait(self) -> _T: ...
     if sys.version_info >= (3, 4):
         @coroutine
         def join(self) -> Generator[Any, None, bool]: ...

third_party/2and3/characteristic/__init__.pyi

@@ -9,7 +9,7 @@ def strip_leading_underscores(attribute_name: AnyStr) -> AnyStr: ...
 
 NOTHING = Any
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
 def attributes(
     attrs: Sequence[Union[AnyStr, Attribute]],
@@ -18,7 +18,7 @@ def attributes(
     apply_with_repr: bool = True,
     apply_immutable: bool = False,
     store_attributes: Optional[Callable[[type, Attribute], Any]] = None,
-    **kw: Optional[dict]) -> Callable[[Type[T]], Type[T]]: ...
+    **kw: Optional[dict]) -> Callable[[Type[_T]], Type[_T]]: ...
 
 class Attribute:
     def __init__(

third_party/2and3/mypy_extensions.pyi

@@ -1,9 +1,9 @@
 from typing import Dict, Type, TypeVar, Union
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
 
-def TypedDict(typename: str, fields: Dict[str, Type[T]]) -> Type[dict]: ...
+def TypedDict(typename: str, fields: Dict[str, Type[_T]]) -> Type[dict]: ...
 
 # Return type that indicates a function does not return.
 # This type is equivalent to the None type, but the no-op Union is necessary to

third_party/3.6/click/core.pyi

@@ -239,8 +239,8 @@ class Command(BaseCommand):
         ...
 
 
-T = TypeVar('T')
-Decorator = Callable[[T], T]
+_T = TypeVar('_T')
+_Decorator = Callable[[_T], _T]
 
 
 class MultiCommand(Command):
@@ -264,7 +264,7 @@ class MultiCommand(Command):
 
     def resultcallback(
         self, replace: bool = False
-    ) -> Decorator:
+    ) -> _Decorator:
         ...
 
     def format_commands(self, ctx: Context, formatter: HelpFormatter) -> None:
@@ -293,10 +293,10 @@ class Group(MultiCommand):
     def add_command(self, cmd: Command, name: str = None):
         ...
 
-    def command(self, *args, **kwargs) -> Decorator:
+    def command(self, *args, **kwargs) -> _Decorator:
         ...
 
-    def group(self, *args, **kwargs) -> Decorator:
+    def group(self, *args, **kwargs) -> _Decorator:
         ...
 
 

third_party/3.6/click/decorators.pyi

@@ -4,21 +4,21 @@ from typing import Any, Callable, Dict, List, TypeVar, Union
 from click.core import Command, Group, Argument, Option, Parameter, Context
 from click.types import ParamType
 
-T = TypeVar('T')
-Decorator = Callable[[T], T]
+_T = TypeVar('_T')
+_Decorator = Callable[[_T], _T]
 
 
-def pass_context(T) -> T:
+def pass_context(_T) -> _T:
     ...
 
 
-def pass_obj(T) -> T:
+def pass_obj(_T) -> _T:
     ...
 
 
 def make_pass_decorator(
     object_type: type, ensure: bool = False
-) -> Callable[[T], T]:
+) -> Callable[[_T], _T]:
     ...
 
 
@@ -34,7 +34,7 @@ def command(
     short_help: str = None,
     options_metavar: str = '[OPTIONS]',
     add_help_option: bool = True,
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -57,7 +57,7 @@ def group(
     short_help: str = None,
     options_metavar: str = '[OPTIONS]',
     add_help_option: bool = True,
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -75,7 +75,7 @@ def argument(
     expose_value: bool = True,
     is_eager: bool = False,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -102,7 +102,7 @@ def option(
     expose_value: bool = True,
     is_eager: bool = False,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -130,7 +130,7 @@ def confirmation_option(
     expose_value: bool = False,
     is_eager: bool = False,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -158,7 +158,7 @@ def password_option(
     expose_value: bool = True,
     is_eager: bool = False,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -188,7 +188,7 @@ def version_option(
     expose_value: bool = False,
     is_eager: bool = True,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...
 
 
@@ -216,5 +216,5 @@ def help_option(
     expose_value: bool = False,
     is_eager: bool = True,
     envvar: Union[str, List[str]] = None
-) -> Decorator:
+) -> _Decorator:
     ...

third_party/3.6/click/termui.pyi

@@ -58,18 +58,18 @@ def echo_via_pager(text: str, color: bool = None) -> None:
     ...
 
 
-T = TypeVar('T')
+_T = TypeVar('_T')
 
 
 @contextmanager
 def progressbar(
-    iterable=Iterable[T],
+    iterable=Iterable[_T],
     length: int = None,
     label: str = None,
     show_eta: bool = True,
     show_percent: bool = None,
     show_pos: bool = False,
-    item_show_func: Callable[[T], str] = None,
+    item_show_func: Callable[[_T], str] = None,
     fill_char: str = '#',
     empty_char: str = '-',
     bar_template: str = '%(label)s  [%(bar)s]  %(info)s',
@@ -77,7 +77,7 @@ def progressbar(
     width: int = 36,
     file: IO = None,
     color: bool = None,
-) -> Generator[T, None, None]:
+) -> Generator[_T, None, None]:
     ...
 
 

third_party/3.6/click/types.pyi

@@ -119,14 +119,14 @@ class File(ParamType):
         ...
 
 
-F = TypeVar('F')  # result of the function
-Func = Callable[[Optional[str]], F]
+_F = TypeVar('_F')  # result of the function
+_Func = Callable[[Optional[str]], _F]
 
 
 class FuncParamType(ParamType):
-    func: Func
+    func: _Func
 
-    def __init__(self, func: Func) -> None:
+    def __init__(self, func: _Func) -> None:
         ...
 
     def __call__(
@@ -134,7 +134,7 @@ class FuncParamType(ParamType):
         value: Optional[str],
         param: Parameter = None,
         ctx: Context = None,
-    ) -> F:
+    ) -> _F:
         ...
 
     def convert(
@@ -142,7 +142,7 @@ class FuncParamType(ParamType):
         value: str,
         param: Optional[Parameter],
         ctx: Optional[Context],
-    ) -> F:
+    ) -> _F:
         ...
 
 
@@ -171,7 +171,7 @@ class IntRange(IntParamType):
         ...
 
 
-PathType = TypeVar('PathType', str, bytes)
+_PathType = TypeVar('_PathType', str, bytes)
 
 
 class Path(ParamType):
@@ -184,11 +184,11 @@ class Path(ParamType):
         readable: bool = True,
         resolve_path: bool = False,
         allow_dash: bool = False,
-        path_type: PathType = None,
+        path_type: _PathType = None,
     ) -> None:
         ...
 
-    def coerce_path_result(self, rv: Union[str, bytes]) -> PathType:
+    def coerce_path_result(self, rv: Union[str, bytes]) -> _PathType:
         ...
 
     def __call__(
@@ -196,7 +196,7 @@ class Path(ParamType):
         value: Optional[str],
         param: Parameter = None,
         ctx: Context = None,
-    ) -> PathType:
+    ) -> _PathType:
         ...
 
     def convert(
@@ -204,7 +204,7 @@ class Path(ParamType):
         value: str,
         param: Optional[Parameter],
         ctx: Optional[Context],
-    ) -> PathType:
+    ) -> _PathType:
         ...
 
 class StringParamType(ParamType):

third_party/3.6/click/utils.pyi

@@ -1,15 +1,15 @@
 from typing import Any, Callable, Iterator, IO, List, Optional, TypeVar, Union
 
 
-T = TypeVar('T')
-Decorator = Callable[[T], T]
+_T = TypeVar('_T')
+_Decorator = Callable[[_T], _T]
 
 
 def _posixify(name: str) -> str:
     ...
 
 
-def safecall(func: T) -> T:
+def safecall(func: _T) -> _T:
     ...
 
 

third_party/3/itsdangerous.pyi

@@ -11,10 +11,10 @@ int_to_byte = Callable[[int], bytes]
 number_types = (int, float)
 izip = zip
 
-bytes_like = Union[bytearray, bytes]
-str_like = Union[str, bytes]
-can_become_bytes = Union[str, bytes, bytearray]
-comparable_bytes = TypeVar('comparable_bytes', str, Union[bytes, bytearray])
+_bytes_like = Union[bytearray, bytes]
+_str_like = Union[str, bytes]
+_can_become_bytes = Union[str, bytes, bytearray]
+_comparable_bytes = TypeVar('_comparable_bytes', str, _bytes_like)
 
 class _CompactJSON:
     def loads(self, payload: Text) -> Any: ...
@@ -23,9 +23,9 @@ class _CompactJSON:
 compact_json = _CompactJSON
 EPOCH = ...  # type: int
 
-def want_bytes(s: can_become_bytes, encoding='', errors='') -> bytes: ...
+def want_bytes(s: _can_become_bytes, encoding='', errors='') -> bytes: ...
 def is_text_serializer(serializer: Any) -> bool: ...
-def constant_time_compare(val1: comparable_bytes, val2: comparable_bytes) -> bool: ...
+def constant_time_compare(val1: _comparable_bytes, val2: _comparable_bytes) -> bool: ...
 
 class BadData(Exception):
     message = ...  # type: str
@@ -50,75 +50,75 @@ class BadHeader(BadSignature):
 
 class SignatureExpired(BadTimeSignature): ...
 
-def base64_encode(string: can_become_bytes) -> bytes: ...
-def base64_decode(string: can_become_bytes) -> bytes: ...
+def base64_encode(string: _can_become_bytes) -> bytes: ...
+def base64_decode(string: _can_become_bytes) -> bytes: ...
 def int_to_bytes(num: int) -> bytes: ...
-def bytes_to_int(bytestr: can_become_bytes) -> bytes: ...
+def bytes_to_int(bytestr: _can_become_bytes) -> bytes: ...
 
 class SigningAlgorithm:
-    def get_signature(self, key: bytes_like, value: bytes_like) -> bytes: ...
-    def verify_signature(self, key: bytes_like, value: bytes_like, sig: can_become_bytes) -> bool: ...
+    def get_signature(self, key: _bytes_like, value: _bytes_like) -> bytes: ...
+    def verify_signature(self, key: _bytes_like, value: _bytes_like, sig: _can_become_bytes) -> bool: ...
 
 class NoneAlgorithm(SigningAlgorithm):
-    def get_signature(self, key: bytes_like, value: bytes_like) -> bytes: ...
+    def get_signature(self, key: _bytes_like, value: _bytes_like) -> bytes: ...
 
 class HMACAlgorithm(SigningAlgorithm):
     default_digest_method = ...  # type: Callable
     digest_method = ...  # type: Callable
     def __init__(self, digest_method: Optional[Callable]=None) -> None: ...
-    def get_signature(self, key: bytes_like, value: bytes_like) -> bytes: ...
+    def get_signature(self, key: _bytes_like, value: _bytes_like) -> bytes: ...
 
 class Signer:
     default_digest_method = ...  # type: Callable
     default_key_derivation = ...  # type: str
-    secret_key = ...  # type: can_become_bytes
-    sep = ...  # type: can_become_bytes
-    salt = ...  # type: can_become_bytes
+    secret_key = ...  # type: _can_become_bytes
+    sep = ...  # type: _can_become_bytes
+    salt = ...  # type: _can_become_bytes
     key_derivation = ...  # type: str
     digest_method = ...  # type: Callable
     algorithm = ...  # type: SigningAlgorithm
-    def __init__(self, secret_key: can_become_bytes, salt: Optional[can_become_bytes]=None, sep: Optional[can_become_bytes]='',
+    def __init__(self, secret_key: _can_become_bytes, salt: Optional[_can_become_bytes]=None, sep: Optional[_can_become_bytes]='',
                  key_derivation: Optional[str]=None,
                  digest_method: Optional[Callable]=None,
                  algorithm: Optional[SigningAlgorithm]=None) -> None: ...
     def derive_key(self) -> bytes: ...
-    def get_signature(self, value: bytes_like) -> bytes: ...
-    def sign(self, value: bytes_like) -> bytes: ...
-    def verify_signature(self, value: bytes_like, sig: can_become_bytes) -> bool: ...
-    def unsign(self, signed_value: can_become_bytes) -> str: ...
-    def validate(self, signed_value: can_become_bytes) -> bool: ...
+    def get_signature(self, value: _bytes_like) -> bytes: ...
+    def sign(self, value: _bytes_like) -> bytes: ...
+    def verify_signature(self, value: _bytes_like, sig: _can_become_bytes) -> bool: ...
+    def unsign(self, signed_value: _can_become_bytes) -> str: ...
+    def validate(self, signed_value: _can_become_bytes) -> bool: ...
 
 class TimestampSigner(Signer):
     def get_timestamp(self) -> int: ...
     def timestamp_to_datetime(self, ts: int) -> datetime: ...
-    def sign(self, value: bytes_like) -> bytes: ...
-    def unsign(self, value: can_become_bytes, max_age: Optional[int]=None, return_timestamp=False) -> Any: ...
-    def validate(self, signed_value: can_become_bytes, max_age: Optional[int]=None) -> bool: ...
+    def sign(self, value: _bytes_like) -> bytes: ...
+    def unsign(self, value: _can_become_bytes, max_age: Optional[int]=None, return_timestamp=False) -> Any: ...
+    def validate(self, signed_value: _can_become_bytes, max_age: Optional[int]=None) -> bool: ...
 
 class Serializer:
     default_serializer = ...  # type: Any
     default_signer = ...  # type: Callable[..., Signer]
     secret_key = ...  # type: Any
-    salt = ...  # type: can_become_bytes
+    salt = ...  # type: _can_become_bytes
     serializer = ...  # type: Any
     is_text_serializer = ...  # type: bool
     signer = ...  # type: Signer
     signer_kwargs = ...  # type: MutableMapping
-    def __init__(self, secret_key: can_become_bytes, salt: Optional[can_become_bytes]=b'', serializer=None, signer: Optional[Callable[..., Signer]]=None, signer_kwargs: Optional[MutableMapping]=None) -> None: ...
+    def __init__(self, secret_key: _can_become_bytes, salt: Optional[_can_become_bytes]=b'', serializer=None, signer: Optional[Callable[..., Signer]]=None, signer_kwargs: Optional[MutableMapping]=None) -> None: ...
     def load_payload(self, payload: Any, serializer=None) -> Any: ...
     def dump_payload(self, *args, **kwargs) -> bytes: ...
-    def make_signer(self, salt: Optional[can_become_bytes]=None) -> Signer: ...
-    def dumps(self, obj: Any, salt: Optional[can_become_bytes]=None) -> str_like: ...
-    def dump(self, obj: Any, f: IO, salt: Optional[can_become_bytes]=None) -> None: ...
-    def loads(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None) -> Any: ...
-    def load(self, f: IO, salt: Optional[can_become_bytes]=None): ...
-    def loads_unsafe(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None) -> Tuple[bool, Any]: ...
+    def make_signer(self, salt: Optional[_can_become_bytes]=None) -> Signer: ...
+    def dumps(self, obj: Any, salt: Optional[_can_become_bytes]=None) -> _str_like: ...
+    def dump(self, obj: Any, f: IO, salt: Optional[_can_become_bytes]=None) -> None: ...
+    def loads(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None) -> Any: ...
+    def load(self, f: IO, salt: Optional[_can_become_bytes]=None): ...
+    def loads_unsafe(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None) -> Tuple[bool, Any]: ...
     def load_unsafe(self, f: IO, *args, **kwargs) -> Tuple[bool, Any]: ...
 
 class TimedSerializer(Serializer):
     default_signer = ...  # type: Callable[..., TimestampSigner]
-    def loads(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None, max_age: Optional[int]=None, return_timestamp=False) -> Any: ...
-    def loads_unsafe(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None, max_age: Optional[int]=None) -> Tuple[bool, Any]: ...
+    def loads(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None, max_age: Optional[int]=None, return_timestamp=False) -> Any: ...
+    def loads_unsafe(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None, max_age: Optional[int]=None) -> Tuple[bool, Any]: ...
 
 class JSONWebSignatureSerializer(Serializer):
     jws_algorithms = ...  # type: MutableMapping[str, SigningAlgorithm]
@@ -126,22 +126,22 @@ class JSONWebSignatureSerializer(Serializer):
     default_serializer = ...  # type: Any
     algorithm_name = ...  # type: str
     algorithm = ...  # type: Any
-    def __init__(self, secret_key: can_become_bytes, salt: Optional[can_become_bytes]=None, serializer=None, signer: Optional[Callable[..., Signer]]=None, signer_kwargs: Optional[MutableMapping]=None, algorithm_name: Optional[str]=None) -> None: ...
+    def __init__(self, secret_key: _can_become_bytes, salt: Optional[_can_become_bytes]=None, serializer=None, signer: Optional[Callable[..., Signer]]=None, signer_kwargs: Optional[MutableMapping]=None, algorithm_name: Optional[str]=None) -> None: ...
     def load_payload(self, payload: Any, return_header=False) -> Any: ...
     def dump_payload(self, *args, **kwargs) -> bytes: ...
     def make_algorithm(self, algorithm_name: str) -> SigningAlgorithm: ...
-    def make_signer(self, salt: Optional[can_become_bytes]=None, algorithm_name: Optional[str]=None) -> Signer: ...
+    def make_signer(self, salt: Optional[_can_become_bytes]=None, algorithm_name: Optional[str]=None) -> Signer: ...
     def make_header(self, header_fields=Optional[MutableMapping]) -> MutableMapping: ...
-    def dumps(self, obj: Any, salt: Optional[can_become_bytes]=None, header_fields=Optional[MutableMapping]) -> str: ...
-    def loads(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None, return_header=False) -> Any: ...
-    def loads_unsafe(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None, return_header=False) -> Tuple[bool, Any]: ...
+    def dumps(self, obj: Any, salt: Optional[_can_become_bytes]=None, header_fields=Optional[MutableMapping]) -> str: ...
+    def loads(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None, return_header=False) -> Any: ...
+    def loads_unsafe(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None, return_header=False) -> Tuple[bool, Any]: ...
 
 class TimedJSONWebSignatureSerializer(JSONWebSignatureSerializer):
     DEFAULT_EXPIRES_IN = ...  # type: int
     expires_in = ...  # type: int
-    def __init__(self, secret_key: can_become_bytes, expires_in: Optional[int]=None, **kwargs) -> None: ...
+    def __init__(self, secret_key: _can_become_bytes, expires_in: Optional[int]=None, **kwargs) -> None: ...
     def make_header(self, header_fields=Optional[MutableMapping]) -> MutableMapping: ...
-    def loads(self, s: can_become_bytes, salt: Optional[can_become_bytes]=None, return_header=False) -> Any: ...
+    def loads(self, s: _can_become_bytes, salt: Optional[_can_become_bytes]=None, return_header=False) -> Any: ...
     def get_issue_date(self, header: MutableMapping) -> Optional[datetime]: ...
     def now(self) -> int: ...