diff --git a/stdlib/hashlib.pyi b/stdlib/hashlib.pyi
index 3b8fbeb0bf3e..4332153d281c 100644
--- a/stdlib/hashlib.pyi
+++ b/stdlib/hashlib.pyi
@@ -3,6 +3,27 @@ from _typeshed import ReadableBuffer, Self
 from typing import AbstractSet
 from typing_extensions import final
 
+__all__ = (
+    "md5",
+    "sha1",
+    "sha224",
+    "sha256",
+    "sha384",
+    "sha512",
+    "blake2b",
+    "blake2s",
+    "sha3_224",
+    "sha3_256",
+    "sha3_384",
+    "sha3_512",
+    "shake_128",
+    "shake_256",
+    "new",
+    "algorithms_guaranteed",
+    "algorithms_available",
+    "pbkdf2_hmac",
+)
+
 class _Hash:
     @property
     def digest_size(self) -> int: ...
diff --git a/stdlib/heapq.pyi b/stdlib/heapq.pyi
index cf2faf7bfc24..a7a787d44e62 100644
--- a/stdlib/heapq.pyi
+++ b/stdlib/heapq.pyi
@@ -2,6 +2,8 @@ from _heapq import *
 from _typeshed import SupportsRichComparison
 from typing import Any, Callable, Iterable, TypeVar
 
+__all__ = ["heappush", "heappop", "heapify", "heapreplace", "merge", "nlargest", "nsmallest", "heappushpop"]
+
 _S = TypeVar("_S")
 
 __about__: str
diff --git a/stdlib/html/__init__.pyi b/stdlib/html/__init__.pyi
index af2a80021656..109c5f4b50fb 100644
--- a/stdlib/html/__init__.pyi
+++ b/stdlib/html/__init__.pyi
@@ -1,4 +1,6 @@
 from typing import AnyStr
 
+__all__ = ["escape", "unescape"]
+
 def escape(s: AnyStr, quote: bool = ...) -> AnyStr: ...
 def unescape(s: AnyStr) -> AnyStr: ...
diff --git a/stdlib/html/entities.pyi b/stdlib/html/entities.pyi
index 1743fccf32b9..be83fd1135be 100644
--- a/stdlib/html/entities.pyi
+++ b/stdlib/html/entities.pyi
@@ -1,3 +1,5 @@
+__all__ = ["html5", "name2codepoint", "codepoint2name", "entitydefs"]
+
 name2codepoint: dict[str, int]
 html5: dict[str, str]
 codepoint2name: dict[int, str]
diff --git a/stdlib/html/parser.pyi b/stdlib/html/parser.pyi
index 60e0de51d3b8..1731a345920b 100644
--- a/stdlib/html/parser.pyi
+++ b/stdlib/html/parser.pyi
@@ -1,6 +1,8 @@
 from _markupbase import ParserBase
 from typing import Pattern
 
+__all__ = ["HTMLParser"]
+
 class HTMLParser(ParserBase):
     def __init__(self, *, convert_charrefs: bool = ...) -> None: ...
     def feed(self, data: str) -> None: ...
diff --git a/stdlib/http/__init__.pyi b/stdlib/http/__init__.pyi
index 93895549cb2a..822cc0932939 100644
--- a/stdlib/http/__init__.pyi
+++ b/stdlib/http/__init__.pyi
@@ -2,6 +2,8 @@ import sys
 from enum import IntEnum
 from typing_extensions import Literal
 
+__all__ = ["HTTPStatus"]
+
 class HTTPStatus(IntEnum):
     @property
     def phrase(self) -> str: ...
diff --git a/stdlib/http/client.pyi b/stdlib/http/client.pyi
index 071c49470462..93f132d678f9 100644
--- a/stdlib/http/client.pyi
+++ b/stdlib/http/client.pyi
@@ -7,6 +7,28 @@ from _typeshed import Self, WriteableBuffer
 from socket import socket
 from typing import IO, Any, BinaryIO, Callable, Iterable, Iterator, Mapping, Protocol, TypeVar, Union, overload
 
+__all__ = [
+    "HTTPResponse",
+    "HTTPConnection",
+    "HTTPException",
+    "NotConnected",
+    "UnknownProtocol",
+    "UnknownTransferEncoding",
+    "UnimplementedFileMode",
+    "IncompleteRead",
+    "InvalidURL",
+    "ImproperConnectionState",
+    "CannotSendRequest",
+    "CannotSendHeader",
+    "ResponseNotReady",
+    "BadStatusLine",
+    "LineTooLong",
+    "RemoteDisconnected",
+    "error",
+    "responses",
+    "HTTPSConnection",
+]
+
 _DataType = Union[bytes, IO[Any], Iterable[bytes], str]
 _T = TypeVar("_T")
 
diff --git a/stdlib/http/cookiejar.pyi b/stdlib/http/cookiejar.pyi
index 02fadd87349a..4fb1c38c6ab8 100644
--- a/stdlib/http/cookiejar.pyi
+++ b/stdlib/http/cookiejar.pyi
@@ -4,6 +4,17 @@ from http.client import HTTPResponse
 from typing import ClassVar, Iterable, Iterator, Pattern, Sequence, TypeVar, overload
 from urllib.request import Request
 
+__all__ = [
+    "Cookie",
+    "CookieJar",
+    "CookiePolicy",
+    "DefaultCookiePolicy",
+    "FileCookieJar",
+    "LWPCookieJar",
+    "LoadError",
+    "MozillaCookieJar",
+]
+
 _T = TypeVar("_T")
 
 class LoadError(OSError): ...
diff --git a/stdlib/http/cookies.pyi b/stdlib/http/cookies.pyi
index 740a41a819ed..11760ecf4287 100644
--- a/stdlib/http/cookies.pyi
+++ b/stdlib/http/cookies.pyi
@@ -4,6 +4,8 @@ from typing import Any, Generic, Iterable, Mapping, TypeVar, Union, overload
 if sys.version_info >= (3, 9):
     from types import GenericAlias
 
+__all__ = ["CookieError", "BaseCookie", "SimpleCookie"]
+
 _DataType = Union[str, Mapping[str, Union[str, Morsel[Any]]]]
 _T = TypeVar("_T")
 
diff --git a/stdlib/http/server.pyi b/stdlib/http/server.pyi
index df9561ce5412..0512ab5f739f 100644
--- a/stdlib/http/server.pyi
+++ b/stdlib/http/server.pyi
@@ -5,6 +5,8 @@ import sys
 from _typeshed import StrPath, SupportsRead, SupportsWrite
 from typing import Any, AnyStr, BinaryIO, ClassVar, Mapping, Sequence
 
+__all__ = ["HTTPServer", "ThreadingHTTPServer", "BaseHTTPRequestHandler", "SimpleHTTPRequestHandler", "CGIHTTPRequestHandler"]
+
 class HTTPServer(socketserver.TCPServer):
     server_name: str
     server_port: int
diff --git a/stdlib/imaplib.pyi b/stdlib/imaplib.pyi
index c36e5cee4fb2..e85e7d4ad90a 100644
--- a/stdlib/imaplib.pyi
+++ b/stdlib/imaplib.pyi
@@ -8,6 +8,8 @@ from types import TracebackType
 from typing import IO, Any, Callable, Pattern, Union
 from typing_extensions import Literal
 
+__all__ = ["IMAP4", "IMAP4_stream", "Internaldate2tuple", "Int2AP", "ParseFlags", "Time2Internaldate", "IMAP4_SSL"]
+
 # TODO: Commands should use their actual return types, not this type alias.
 #       E.g. Tuple[Literal["OK"], List[bytes]]
 _CommandResults = tuple[str, list[Any]]
diff --git a/stdlib/imghdr.pyi b/stdlib/imghdr.pyi
index 4515cf2269b0..af046e899326 100644
--- a/stdlib/imghdr.pyi
+++ b/stdlib/imghdr.pyi
@@ -1,6 +1,8 @@
 from _typeshed import StrPath
 from typing import Any, BinaryIO, Callable, Protocol, overload
 
+__all__ = ["what"]
+
 class _ReadableBinary(Protocol):
     def tell(self) -> int: ...
     def read(self, size: int) -> bytes: ...
diff --git a/stdlib/importlib/__init__.pyi b/stdlib/importlib/__init__.pyi
index 1b91cc55f2df..0e99786775b0 100644
--- a/stdlib/importlib/__init__.pyi
+++ b/stdlib/importlib/__init__.pyi
@@ -2,6 +2,8 @@ from importlib.abc import Loader
 from types import ModuleType
 from typing import Mapping, Sequence
 
+__all__ = ["__import__", "import_module", "invalidate_caches", "reload"]
+
 # Signature of `builtins.__import__` should be kept identical to `importlib.__import__`
 def __import__(
     name: str,
diff --git a/stdlib/importlib/resources.pyi b/stdlib/importlib/resources.pyi
index 38b891fb72e7..cee3259332ff 100644
--- a/stdlib/importlib/resources.pyi
+++ b/stdlib/importlib/resources.pyi
@@ -5,6 +5,38 @@ from pathlib import Path
 from types import ModuleType
 from typing import Any, BinaryIO, Iterator, TextIO, Union
 
+if sys.version_info >= (3, 10):
+    __all__ = [
+        "Package",
+        "Resource",
+        "ResourceReader",
+        "as_file",
+        "contents",
+        "files",
+        "is_resource",
+        "open_binary",
+        "open_text",
+        "path",
+        "read_binary",
+        "read_text",
+    ]
+elif sys.version_info >= (3, 9):
+    __all__ = [
+        "Package",
+        "Resource",
+        "as_file",
+        "contents",
+        "files",
+        "is_resource",
+        "open_binary",
+        "open_text",
+        "path",
+        "read_binary",
+        "read_text",
+    ]
+else:
+    __all__ = ["Package", "Resource", "contents", "is_resource", "open_binary", "open_text", "path", "read_binary", "read_text"]
+
 Package = Union[str, ModuleType]
 Resource = Union[str, os.PathLike[Any]]
 
diff --git a/stdlib/io.pyi b/stdlib/io.pyi
index 659248015e25..c32691edb686 100644
--- a/stdlib/io.pyi
+++ b/stdlib/io.pyi
@@ -7,6 +7,50 @@ from types import TracebackType
 from typing import IO, Any, BinaryIO, Callable, Iterable, Iterator, TextIO
 from typing_extensions import Literal
 
+if sys.version_info >= (3, 8):
+    __all__ = [
+        "BlockingIOError",
+        "open",
+        "open_code",
+        "IOBase",
+        "RawIOBase",
+        "FileIO",
+        "BytesIO",
+        "StringIO",
+        "BufferedIOBase",
+        "BufferedReader",
+        "BufferedWriter",
+        "BufferedRWPair",
+        "BufferedRandom",
+        "TextIOBase",
+        "TextIOWrapper",
+        "UnsupportedOperation",
+        "SEEK_SET",
+        "SEEK_CUR",
+        "SEEK_END",
+    ]
+else:
+    __all__ = [
+        "BlockingIOError",
+        "open",
+        "IOBase",
+        "RawIOBase",
+        "FileIO",
+        "BytesIO",
+        "StringIO",
+        "BufferedIOBase",
+        "BufferedReader",
+        "BufferedWriter",
+        "BufferedRWPair",
+        "BufferedRandom",
+        "TextIOBase",
+        "TextIOWrapper",
+        "UnsupportedOperation",
+        "SEEK_SET",
+        "SEEK_CUR",
+        "SEEK_END",
+    ]
+
 DEFAULT_BUFFER_SIZE: Literal[8192]
 
 SEEK_SET: Literal[0]