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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 PassphraseCallback(verify=False, prompt1="Enter passphrase:", prompt2="Verify passphrase:"):
 """A utility function to read a passphrase from stdin."""

  while 1:
    try:
      p1 = getpass.getpass(prompt1)
      if verify:
        p2 = getpass.getpass(prompt2)
        if p1 == p2:
          break
      else:
        break
    except KeyboardInterrupt:
      return None
  return p1