--- /dev/null
+import sys
+
+class MessageError(Exception): ...
+class MessageParseError(MessageError): ...
+class HeaderParseError(MessageParseError): ...
+class BoundaryError(MessageParseError): ...
+class MultipartConversionError(MessageError, TypeError): ...
+class CharsetError(MessageError): ...
+
+class MessageDefect(ValueError):
+ def __init__(self, line: str | None = ...) -> None: ...
+
+class NoBoundaryInMultipartDefect(MessageDefect): ...
+class StartBoundaryNotFoundDefect(MessageDefect): ...
+class FirstHeaderLineIsContinuationDefect(MessageDefect): ...
+class MisplacedEnvelopeHeaderDefect(MessageDefect): ...
+class MultipartInvariantViolationDefect(MessageDefect): ...
+class InvalidMultipartContentTransferEncodingDefect(MessageDefect): ...
+class UndecodableBytesDefect(MessageDefect): ...
+class InvalidBase64PaddingDefect(MessageDefect): ...
+class InvalidBase64CharactersDefect(MessageDefect): ...
+class InvalidBase64LengthDefect(MessageDefect): ...
+class CloseBoundaryNotFoundDefect(MessageDefect): ...
+class MissingHeaderBodySeparatorDefect(MessageDefect): ...
+
+MalformedHeaderDefect = MissingHeaderBodySeparatorDefect
+
+class HeaderDefect(MessageDefect): ...
+class InvalidHeaderDefect(HeaderDefect): ...
+class HeaderMissingRequiredValue(HeaderDefect): ...
+
+class NonPrintableDefect(HeaderDefect):
+ def __init__(self, non_printables: str | None) -> None: ...
+
+class ObsoleteHeaderDefect(HeaderDefect): ...
+class NonASCIILocalPartDefect(HeaderDefect): ...
+
+if sys.version_info >= (3, 10):
+ class InvalidDateDefect(HeaderDefect): ...