<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def deserialize(self, mutagen_value):
 """Given a raw value stored on a Mutagen object, decode and return the represented value. """

        if self.suffix and isinstance(mutagen_value, six.text_type) \
           and mutagen_value.endswith(self.suffix):
            return mutagen_value[:-len(self.suffix)]
        else:
            return mutagen_value