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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 to_python(self, value):
 """ Convert a string from the database to a Python value. """

        if value == "":
            return None

        try:
            if isinstance(value, six.string_types):
                return self.deserializer(value)
            elif isinstance(value, bytes):
                return self.deserializer(value.decode('utf8'))
        except ValueError:
            pass
        return value