The __getattr__ hack is not needed. You can reset the flags in a different, more straight forward way:


class ReproducibleZipInfo(ZipInfo):
    __slots__ = ()

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self._reset_flags()

    @classmethod
    def from_file(cls, *args, **kwargs):
        zinfo = super().from_file(*args, **kwargs)
        zinfo._reset_flags()
        return zinfo

    def _reset_flags(self):
        self.date_time = (1980, 0, 0, 0, 0, 0)
        self.create_system = 0
        self.external_attr = 0


>>> zinfo = ReproducibleZipInfo.from_file("/etc/os-release")
>>> zinfo.external_attr
0
>>> zinfo.create_system
0
>>> zinfo.date_time
(1980, 0, 0, 0, 0, 0)


I think it makes also sense to replace hard-coded ZipInfo class with dispatcher attribute on the class:


@@ -1203,6 +1211,7 @@ class ZipFile:
 
     fp = None                   # Set here since __del__ checks it
     _windows_illegal_name_trans_table = None
+    zipinfo_class = ZipInfo
 
     def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=True,
                  compresslevel=None, *, strict_timestamps=True):
@@ -1362,7 +1371,7 @@ def _RealGetContents(self):
                 # Historical ZIP filename encoding
                 filename = filename.decode('cp437')
             # Create ZipInfo instance to store file information
-            x = ZipInfo(filename)
+            x = self.zipinfo_class(filename)