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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 contribute_to_class(self, cls, name, **kwargs):
 """ Add a decrypted field proxy to the model. Add to the field model an `EncryptedProxyField` to get the decrypted values of the field. The decrypted value can be accessed using the field's name attribute on the model instance. """

        super(PGPMixin, self).contribute_to_class(cls, name, **kwargs)
        setattr(cls, self.name, self.descriptor_class(field=self))