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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 clean_email(self):
 """ Validate that the email address is unique. """

        if get_user_model().objects.filter(
            Q(email__iexact=self.cleaned_data['email']) |
            Q(email_unconfirmed__iexact=self.cleaned_data['email'])):
            raise forms.ValidationError(_(u'This email address is already '
                        'in use. Please supply a different email.'))
        return self.cleaned_data['email']