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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 _verify_encoding(self, enc):
 """Verify encoding is okay."""


        enc = PYTHON_ENCODING_NAMES.get(enc, enc)
        try:
            codecs.getencoder(enc)
            encoding = enc
        except LookupError:
            encoding = None
        return encoding