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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 FindUniqueId(dic):
 """Return a string not used as a key in the dictionary dic"""

  name = str(len(dic))
  while name in dic:
    # Use bigger numbers so it is obvious when an id is picked randomly.
    name = str(random.randint(1000000, 999999999))
  return name