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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 quoted(s):
 """ quotes a string if necessary. """

    # strip any existing quotes
    s = s.strip(u'"')
    # don't add quotes for minus or leading space
    if s[0] in (u'-', u' '):
        return s
    if u' ' in s or u'/' in s:
        return u'"%s"' % s
    else:
        return s