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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def match_file(self, f, update_file=False):
 """ Determine whether the passed file matches the Entity. Args: f (File):
 The File instance to match against. Returns: the matched value if a match was found, otherwise None. """

        if self.map_func is not None:
            val = self.map_func(f)
        else:
            m = self.regex.search(f.path)
            val = m.group(1) if m is not None else None

        return self._astype(val)