clean python 3 specific stuff from stdlib/@python2 stubs (#5451)

stdlib/@python2/dis.pyi

@@ -16,68 +16,19 @@ from opcode import (
 )
 from typing import IO, Any, Callable, Dict, Iterator, List, NamedTuple, Optional, Tuple, Union
 
-if sys.version_info >= (3, 4):
-    from opcode import stack_effect as stack_effect
-
-if sys.version_info >= (3, 6):
-    from opcode import hasnargs as hasnargs
-
 # Strictly this should not have to include Callable, but mypy doesn't use FunctionType
 # for functions (python/mypy#3171)
 _have_code = Union[types.MethodType, types.FunctionType, types.CodeType, type, Callable[..., Any]]
 _have_code_or_string = Union[_have_code, str, bytes]
 
-if sys.version_info >= (3, 4):
-    class Instruction(NamedTuple):
-        opname: str
-        opcode: int
-        arg: Optional[int]
-        argval: Any
-        argrepr: str
-        offset: int
-        starts_line: Optional[int]
-        is_jump_target: bool
-    class Bytecode:
-        codeobj: types.CodeType
-        first_line: int
-        def __init__(
-            self, x: _have_code_or_string, *, first_line: Optional[int] = ..., current_offset: Optional[int] = ...
-        ) -> None: ...
-        def __iter__(self) -> Iterator[Instruction]: ...
-        def __repr__(self) -> str: ...
-        def info(self) -> str: ...
-        def dis(self) -> str: ...
-        @classmethod
-        def from_traceback(cls, tb: types.TracebackType) -> Bytecode: ...
-
 COMPILER_FLAG_NAMES: Dict[int, str]
 
 def findlabels(code: _have_code) -> List[int]: ...
 def findlinestarts(code: _have_code) -> Iterator[Tuple[int, int]]: ...
+def dis(x: _have_code_or_string = ...) -> None: ...
+def distb(tb: types.TracebackType = ...) -> None: ...
+def disassemble(co: _have_code, lasti: int = ...) -> None: ...
+def disco(co: _have_code, lasti: int = ...) -> None: ...
 
 if sys.version_info >= (3, 0):
-    def pretty_flags(flags: int) -> str: ...
-    def code_info(x: _have_code_or_string) -> str: ...
-
-if sys.version_info >= (3, 7):
-    def dis(x: Optional[_have_code_or_string] = ..., *, file: Optional[IO[str]] = ..., depth: Optional[int] = ...) -> None: ...
-
-elif sys.version_info >= (3, 4):
-    def dis(x: Optional[_have_code_or_string] = ..., *, file: Optional[IO[str]] = ...) -> None: ...
-
-else:
-    def dis(x: _have_code_or_string = ...) -> None: ...
-
-if sys.version_info >= (3, 4):
-    def distb(tb: Optional[types.TracebackType] = ..., *, file: Optional[IO[str]] = ...) -> None: ...
-    def disassemble(co: _have_code, lasti: int = ..., *, file: Optional[IO[str]] = ...) -> None: ...
-    def disco(co: _have_code, lasti: int = ..., *, file: Optional[IO[str]] = ...) -> None: ...
-    def show_code(co: _have_code, *, file: Optional[IO[str]] = ...) -> None: ...
-    def get_instructions(x: _have_code, *, first_line: Optional[int] = ...) -> Iterator[Instruction]: ...
-
-else:
-    def distb(tb: types.TracebackType = ...) -> None: ...
-    def disassemble(co: _have_code, lasti: int = ...) -> None: ...
-    def disco(co: _have_code, lasti: int = ...) -> None: ...
-    if sys.version_info >= (3, 0):
-        def show_code(co: _have_code) -> None: ...
+    def show_code(co: _have_code) -> None: ...