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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_type(self):
 """ Extract the ``FORM_TYPE`` from the fields. :return: ``FORM_TYPE`` value or :data:`None` :rtype: :class:`str` or :data:`None` Return :data:`None` if no well-formed ``FORM_TYPE`` field is found in the list of fields. .. versionadded:: 0.8 """


        for field in self.fields:
            if field.var == "FORM_TYPE" and field.type_ == FieldType.HIDDEN:
                if len(field.values) != 1:
                    return None
                return field.values[0]