Add the form attribute to the UNTL Python object.

def add_form(self, **kwargs):
        """Add the form attribute to the UNTL Python object."""
        vocabularies = kwargs.get('vocabularies', None)
        qualifier = kwargs.get('qualifier', None)
        content = kwargs.get('content', None)
        parent_tag = kwargs.get('parent_tag', None)
        superuser = kwargs.get('superuser', False)
        # Element has both the qualifier and content.
        if qualifier is not None and content is not None:
            # Create the form attribute.
            self.form = UNTL_FORM_DISPATCH[self.tag](
                vocabularies=vocabularies,
                qualifier_value=qualifier,
                input_value=content,
                untl_object=self,
                superuser=superuser,
            )
        # Element just has a qualifier.
        elif qualifier is not None:
            # Create the form attribute.
            self.form = UNTL_FORM_DISPATCH[self.tag](
                vocabularies=vocabularies,
                qualifier_value=qualifier,
                untl_object=self,
                superuser=superuser,
            )
        # Element just has content.
        elif content is not None:
            # If the element is a child element,
            # create the form attribute.
            if parent_tag is None:
                self.form = UNTL_FORM_DISPATCH[self.tag](
                    vocabularies=vocabularies,
                    input_value=content,
                    untl_object=self,
                    superuser=superuser,
                )
            else:
                # Create the form attribute.
                self.form = UNTL_FORM_DISPATCH[self.tag](
                    vocabularies=vocabularies,
                    input_value=content,
                    untl_object=self,
                    parent_tag=parent_tag,
                    superuser=superuser,
                )
        # Element has children and no qualifiers or content
        # or is blank (not originally in the UNTL record).
        else:
            # Element is a child element.
            if parent_tag is None:
                # Create the form attribute.
                self.form = UNTL_FORM_DISPATCH[self.tag](
                    vocabularies=vocabularies,
                    untl_object=self,
                    superuser=superuser,
                )
            else:
                # Create the form attribute.
                self.form = UNTL_FORM_DISPATCH[self.tag](
                    vocabularies=vocabularies,
                    untl_object=self,
                    parent_tag=parent_tag,
                    superuser=superuser,
                )