When cleaned_data is initially accessed, we want to ensure the form
        gets validated which has the side effect of setting cleaned_data to
        something.

def cleaned_data(self):
        """
        When cleaned_data is initially accessed, we want to ensure the form
        gets validated which has the side effect of setting cleaned_data to
        something.
        """
        if not hasattr(self, "_cleaned_data"):
            self._cleaned_data = {}
            self.is_valid()
        return self._cleaned_data