Zとgzに対応する: loading both Z/gz compressed file

gistfile1.txt

    # 汚くて発狂しそう
    def open_zfiles(filename):
        open_method = open # builtin open
        if filename.endswith('gz'):
            open_method = gzip.open # gzip's open
        elif filename.endswith('Z'):
            from subprocess import Popen, PIPE
            open_method = lambda fn: Popen(['zcat', fn], stdout=PIPE).stdout
        with open_method(filename, 'rb') as infile:
            return infile