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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 xml_path_completion(xml_path):
 """ Takes in a local xml path and returns a full path. if @xml_path is absolute, do nothing if @xml_path is not absolute, load xml that is shipped by the package """

    if xml_path.startswith("/"):
        full_path = xml_path
    else:
        full_path = os.path.join(robosuite.models.assets_root, xml_path)
    return full_path