argparse: add |str to SUPPRESS type

Author: not-my-profile

stdlib/argparse.pyi

@@ -68,7 +68,8 @@ OPTIONAL: Literal["?"]
 PARSER: Literal["A..."]
 REMAINDER: Literal["..."]
 _SUPPRESS_T = NewType("_SUPPRESS_T", str)
-SUPPRESS: _SUPPRESS_T  # not using Literal because argparse sometimes compares SUPPRESS with is
+SUPPRESS: _SUPPRESS_T | str  # not using Literal because argparse sometimes compares SUPPRESS with is
+# the | str is there so that foo = argparse.SUPPRESS; foo = "test" checks out in mypy
 ZERO_OR_MORE: Literal["*"]
 _UNRECOGNIZED_ARGS_ATTR: str  # undocumented
 

tests/stubtest_allowlists/py3_common.txt

@@ -236,7 +236,6 @@ xml.parsers.expat.expat_CAPI
 # Allowlist entries that cannot or should not be fixed
 # ==========
 _pydecimal.*  # See comments in file
-argparse.SUPPRESS  # See comment in file
 ast.NodeVisitor.visit_\w+  # Methods are discovered dynamically, see #3796
 # Weird special builtins that are typed as functions, but aren't functions
 builtins.copyright