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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_tshark_interfaces(tshark_path=None):
 """ Returns a list of interface numbers from the output tshark -D. Used internally to capture on multiple interfaces. """

    parameters = [get_process_path(tshark_path), '-D']
    with open(os.devnull, 'w') as null:
        tshark_interfaces = subprocess.check_output(parameters, stderr=null).decode("utf-8")

    return [line.split('.')[0] for line in tshark_interfaces.splitlines()]