def chk_int(line):

    """Function:  chk_int

    Description:  Checks to see if the string is an integer.
        NOTE:   Does not work for floats.

    Arguments:
        (input) line -> String containing an integer.
        (output) True|False -> Whether the string is an integer.

    """

    # Remove positive/negative sign if present.
    if line[0] in ("-", "+"):
        return line[1:].isdigit()

    return line.isdigit()