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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 sphinx_class(self):
 """Redefine sphinx class so documentation links to instance_class"""

        classdoc = ':class:`{cls} <{pref}.{cls}>`'.format(
            cls=self.instance_class.__name__,
            pref=self.instance_class.__module__,
        )
        return classdoc