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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def ValidUserResponse(response, validList):
 """ Check if user response is in a list of valid entires. If an invalid response is given re-prompt user to enter one of the valid options. Do not proceed until a valid entry is given. Parameters response : string Response string to check. validList : list A list of valid responses. Returns string A valid response string. """

  if response in validList:
    return response
  else:
    prompt = "Unknown response given - please reenter one of [{0}]: ".format('/'.join(validList))
    response = goodlogging.Log.Input("DM", prompt)
    return ValidUserResponse(response, validList)