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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 _get_matcher(self, target):
 """Get deep match."""


        if target is None:
            matcher = None
        elif isinstance(target, (str, bytes)):
            # Plain text match
            if not self.case_sensitive:
                match = target.lower()
            else:
                match = target
            matcher = functools.partial(self._match_literal, b=match)
        else:
            # File match pattern
            matcher = target.match
        return matcher