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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 _set_ndb_cache_policy():
 """Tell NDB to never cache anything in memcache or in-process. This ensures that entities fetched from Datastore input_readers via NDB will not bloat up the request memory size and Datastore Puts will avoid doing calls to memcache. Without this you get soft memory limit exits, which hurts overall throughput. """

  ndb_ctx = ndb.get_context()
  ndb_ctx.set_cache_policy(lambda key: False)
  ndb_ctx.set_memcache_policy(lambda key: False)