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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_validation_errors(self, xml_input):
 """ This method returns a list of validation errors. If there are no errors an empty list is returned """

        errors = []
        try:
            parsed_xml = etree.parse(self._handle_xml(xml_input))
            self.xmlschema.assertValid(parsed_xml)
        except (etree.DocumentInvalid, etree.XMLSyntaxError), e:
            errors = self._handle_errors(e.error_log)
        except AttributeError:
            raise CannotValidate('Set XSD to validate the XML')
        return errors