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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 get_stdin_data():
 """ Helper function that returns data send to stdin or False if nothing is send """

    # STDIN can only be 3 different types of things ("modes")
    #  1. An interactive terminal device (i.e. a TTY -> sys.stdin.isatty() or stat.S_ISCHR)
    #  2. A (named) pipe (stat.S_ISFIFO)
    #  3. A regular file (stat.S_ISREG)
    # Technically, STDIN can also be other device type like a named unix socket (stat.S_ISSOCK), but we don't
    # support that in gitlint (at least not today).
    #
    # Now, the behavior that we want is the following:
    # If someone sends something directly to gitlint via a pipe or a regular file, read it. If not, read from the
    # local repository.
    # Note that we don't care about whether STDIN is a TTY or not, we only care whether data is via a pipe or regular
    # file.
    # However, in case STDIN is not a TTY, it HAS to be one of the 2 other things (pipe or regular file), even if
    # no-one is actually sending anything to gitlint over them. In this case, we still want to read from the local
    # repository.
    # To support this use-case (which is common in CI runners such as Jenkins and Gitlab), we need to actually attempt
    # to read from STDIN in case it's a pipe or regular file. In case that fails, then we'll fall back to reading
    # from the local repo.

    mode = os.fstat(sys.stdin.fileno()).st_mode
    stdin_is_pipe_or_file = stat.S_ISFIFO(mode) or stat.S_ISREG(mode)
    if stdin_is_pipe_or_file:
        input_data = sys.stdin.read()
        # Only return the input data if there's actually something passed
        # i.e. don't consider empty piped data
        if input_data:
            return ustr(input_data)
    return False