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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(content, source=None):
 """Parses the XML text using the ET.XML function, but handling the ParseError in a user-friendly way. """

    try:
        tree = ET.XML(content)
    except ET.ParseError as err:
        x_parse_error(err, content, source)
    return tree