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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def calcMD5(path):
 """ calc MD5 based on path """

    # check that file exists
    if os.path.exists(path) is False:
        yield False
    else:
        command = ['md5sum', path]
        p = Popen(command, stdout = PIPE)
        for line in p.communicate()[0].splitlines():
            yield line.decode('ascii').strip().split()[0]
        p.wait()
        yield False