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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 percent_encode(text, encode_set=DEFAULT_ENCODE_SET, encoding='utf-8'):
    '''Percent encode text.

    Unlike Python's ``quote``, this function accepts a blacklist instead of
    a whitelist of safe characters.
    '''
    byte_string = text.encode(encoding)

    try:
        mapping = _percent_encoder_map_cache[encode_set]
    except KeyError:
        mapping = _percent_encoder_map_cache[encode_set] = PercentEncoderMap(
            encode_set).__getitem__

    return ''.join([mapping(char) for char in byte_string])