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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 get(self, key):
    '''Return the object named by key. Checks each datastore in order.'''
    value = None
    for store in self._stores:
      value = store.get(key)
      if value is not None:
        break

    # add model to lower stores only
    if value is not None:
      for store2 in self._stores:
        if store == store2:
          break
        store2.put(key, value)

    return value