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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 xsd_error_log_string(xsd_error_log):
 """Return a human-readable string representation of the error log returned by lxml's XMLSchema validator. """

    ret = []
    for error in xsd_error_log:
        ret.append(
            "ERROR ON LINE {}: {}".format(error.line, error.message.encode("utf-8"))
        )
    return "\n".join(ret)