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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 post_mortem(traceback):
 """Work with an exception in a post-mortem debugger. Try to use `ipdb` first, falling back to `pdb`. """

    try:
        from ipdb import post_mortem
    except ImportError:
        from pdb import post_mortem

    message = "Entering post-mortem debugger. Type `help` for help."
    redline = colorized("{autored}%s{/autored}") % "{0:=^{1}}"

    print()
    print(redline.format(" CRASH! ", len(message)))
    print(message)
    print(redline.format("", len(message)))
    print()

    post_mortem(traceback)