lass:`CloseMatch` takes parameters:

    - ``match_string`` - string to be matched
    - ``caseless`` - a boolean indicating whether to ignore casing when comparing characters
    - ``max_mismatches`` - (``default=1``) maximum number of
      mismatches allowed to count as a match

    The results from a successful parse will contain the matched text
    from the input string and the following named results:

    - ``mismatches`` - a list of the positions within the
      match_string where mismatches were found
    - ``original`` - the original match_string used to 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']})
    Nr