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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 remove_field(self, field):
 """ Removes a field from this table :param field: This can be a string of a field name, a dict of {'alias': field}, or a ``Field`` instance :type field: str or dict or :class:`Field <querybuilder.fields.Field>` """

        new_field = FieldFactory(
            field,
        )
        new_field.set_table(self)
        new_field_identifier = new_field.get_identifier()
        for field in self.fields:
            if field.get_identifier() == new_field_identifier:
                self.fields.remove(field)
                return field
        return None