def guess_minimum_encoding(text, charsets=('ascii', 'latin1', 'utf8')):
    """Try to guess the minimum charset that is able to represent.

    Try to guess the minimum charset that is able to represent the given
    text using the provided charsets. text is supposed to be encoded in utf8.
    Returns (encoded_text, charset) where charset is the first charset
    in the sequence being able to encode text.
    Returns (text_in_utf8, 'utf8') in case no charset is able to encode text.

    @note: If the input text is not in strict UTF-8, then replace any
        non-UTF-8 chars inside it.
    """
    text_in_unicode = text.decode('utf8', 'replace')
    for charset in charsets:
        try:
            return text_in_unicode.encode(charset), charset
        except (UnicodeEncodeError, UnicodeDecodeError):
            pass
    return text_in_unicode.encode('utf8'), 'utf8'
