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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 quote_xml(text):
 """Format a value for display as an XML text node. Returns: Unicode string (str on Python 3, unicode on Python 2) """

    text = _coerce_unicode(text)

    # If it's a CDATA block, return the text as is.
    if text.startswith(CDATA_START):
        return text

    # If it's not a CDATA block, escape the XML and return the character
    # encoded string.
    return saxutils.escape(text)