Re-organize directory structure (#4971)

See discussion in #2491

Co-authored-by: Ivan Levkivskyi <ilevkivskyi@dropbox.com>

stdlib/tracemalloc.pyi

@@ -0,0 +1,86 @@
+import sys
+from typing import List, Optional, Sequence, Tuple, Union, overload
+
+from _tracemalloc import *
+
+def get_object_traceback(obj: object) -> Optional[Traceback]: ...
+def take_snapshot() -> Snapshot: ...
+
+class DomainFilter:
+    inclusive: bool
+    domain: int
+    def __init__(self, inclusive: bool, domain: int) -> None: ...
+
+class Filter:
+    domain: Optional[int]
+    inclusive: bool
+    lineno: Optional[int]
+    filename_pattern: str
+    all_frames: bool
+    def __init__(
+        self,
+        inclusive: bool,
+        filename_pattern: str,
+        lineno: Optional[int] = ...,
+        all_frames: bool = ...,
+        domain: Optional[int] = ...,
+    ) -> None: ...
+
+class Statistic:
+    count: int
+    size: int
+    traceback: Traceback
+    def __init__(self, traceback: Traceback, size: int, count: int) -> None: ...
+
+class StatisticDiff:
+    count: int
+    count_diff: int
+    size: int
+    size_diff: int
+    traceback: Traceback
+    def __init__(self, traceback: Traceback, size: int, size_diff: int, count: int, count_diff: int) -> None: ...
+
+_FrameTupleT = Tuple[str, int]
+
+class Frame:
+    filename: str
+    lineno: int
+    def __init__(self, frame: _FrameTupleT) -> None: ...
+
+if sys.version_info >= (3, 9):
+    _TraceTupleT = Union[Tuple[int, int, Sequence[_FrameTupleT], Optional[int]], Tuple[int, int, Sequence[_FrameTupleT]]]
+else:
+    _TraceTupleT = Tuple[int, int, Sequence[_FrameTupleT]]
+
+class Trace:
+    domain: int
+    size: int
+    traceback: Traceback
+    def __init__(self, trace: _TraceTupleT) -> None: ...
+
+class Traceback(Sequence[Frame]):
+    if sys.version_info >= (3, 9):
+        total_nframe: Optional[int]
+        def __init__(self, frames: Sequence[_FrameTupleT], total_nframe: Optional[int] = ...) -> None: ...
+    else:
+        def __init__(self, frames: Sequence[_FrameTupleT]) -> None: ...
+    if sys.version_info >= (3, 7):
+        def format(self, limit: Optional[int] = ..., most_recent_first: bool = ...) -> List[str]: ...
+    else:
+        def format(self, limit: Optional[int] = ...) -> List[str]: ...
+    @overload
+    def __getitem__(self, i: int) -> Frame: ...
+    @overload
+    def __getitem__(self, s: slice) -> Sequence[Frame]: ...
+    def __len__(self) -> int: ...
+
+class Snapshot:
+    def __init__(self, traces: Sequence[_TraceTupleT], traceback_limit: int) -> None: ...
+    def compare_to(self, old_snapshot: Snapshot, key_type: str, cumulative: bool = ...) -> List[StatisticDiff]: ...
+    def dump(self, filename: str) -> None: ...
+    def filter_traces(self, filters: Sequence[Union[DomainFilter, Filter]]) -> Snapshot: ...
+    @staticmethod
+    def load(filename: str) -> Snapshot: ...
+    def statistics(self, key_type: str, cumulative: bool = ...) -> List[Statistic]: ...
+    traceback_limit: int
+    traces: Sequence[Trace]