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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 hexedit(x):
 """Run external hex editor on a packet or bytes. Set editor in conf.prog.hexedit"""

    x = bytes(x)
    fname = get_temp_file()
    with open(fname,"wb") as f:
      f.write(x)
    subprocess.call([conf.prog.hexedit, fname])
    with open(fname, "rb") as f:
      x = f.read()
    return x