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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_attribute(self, element, attribute):
 """Retrieve the value of an attribute that is contained by the tag element. :param string element: Name of an xml element. :param string attribute: Name of the attribute that is to be returned. :return: Desired attribute value. :rtype: string """

    parsed_element = self.parsed.getElementsByTagName(element)
    if not parsed_element:
      raise self.XmlError("There is no '{0}' element in "
                          "xml file at: {1}".format(element, self.xml_path))
    parsed_attribute = parsed_element[0].getAttribute(attribute)
    if not parsed_attribute:
      raise self.XmlError("There is no '{0}' attribute in "
                          "xml at: {1}".format(attribute, self.xml_path))
    return parsed_attribute