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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(code):
 """Returns quoted code if not already quoted and if possible Parameters code: String \tCode thta is quoted """


    try:
        code = code.rstrip()

    except AttributeError:
        # code is not a string, may be None --> There is no code to quote
        return code

    if code and code[0] + code[-1] not in ('""', "''", "u'", '"') \
       and '"' not in code:
        return 'u"' + code + '"'
    else:
        return code