script.py

import re,base64, quopri


def encoded_words_to_text(encoded_words):
    encoded_word_regex = r'=\?{1}(.+)\?{1}([B|Q])\?{1}(.+)\?{1}='
    charset, encoding, encoded_text = re.match(encoded_word_regex, encoded_words).groups()
    if encoding is 'B':
        byte_string = base64.b64decode(encoded_text)
    elif encoding is 'Q':
        byte_string = quopri.decodestring(encoded_text)
    else:
        raise ValueError
    return byte_string.decode(charset)


print(encoded_words_to_text('=?UTF-8?B?0LLQtdGI0LjQstCw0L3QuNC1LlhMUw==?='))