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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_xml_child(source, path):
 """Get the first descendant of source identified by path. Path must be either a an xpath string, or a 2-tuple of (xpath, namespace_dict). """

  if isinstance(path, (tuple, list)):
    return source.find(*path)
  else:
    return source.find(path)