o compare
      against the input string

    If ``mismatches`` is an empty list, then the match was an exact
    match.

    Example::

        patt = CloseMatch("ATCATCGAATGGA")
        patt.parse_string("ATCATCGAAXGGA") # -> (['ATCATCGAAXGGA'], {'mismatches': [[9]], 'original': ['ATCATCGAATGGA']})
        patt.parse_string("ATCAXCGAAXGGA") # -> Exception: Expected 'ATCATCGAATGGA' (with up to 1 mismatches) (at char 0), (line:1, col:1)

        # exact match
        patt.parse_string("ATCATCGAATGGA") # -> (['ATCATCGAATGGA'], {'mismatches': [[]], 'original': ['ATCATCGAATGGA']})

        # close match allowing up to 2 mismatches
        patt = CloseMatch("ATCATCGAATGGA", max_mismatches=2)
        patt.parse_string("ATCAXCGAAXGGA") # -> (['ATCAXCGAAXGGA'], {'mismatches': [[4, 9]], 'original': ['ATCATCGAATGGA']})
    r