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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 get_form_class(self):
 """ Returns form class to use in the view. :rtype: django.forms.ModelForm. """

        if self.object.link_type == Link.LINK_TYPE_EMAIL:
            return EmailLinkForm
        elif self.object.link_type == Link.LINK_TYPE_EXTERNAL:
            return ExternalLinkForm

        return None