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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 pct_encode(s, encdct):
 """ Return a translated version of s where each character is mapped to a string thanks to the encdct dictionary. Use the encdct parameter to construct a string from parameter s where each character k from s is replaced by the value corresponding to key k in encdct. It happens that callers use dictionaries smartly constructed so that this function will perform percent-encoding quickly when called whith such a dictionary. """

    if s is None:
        return None
    elif not isinstance(s, unicode):
        s = str(s)
    else:
        s = s.encode('utf8')

    return ''.join(map(encdct.__getitem__, s))