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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 _filter_and_bucket_subtokens(subtoken_counts, min_count):
 """Return a bucketed list of subtokens that are filtered by count. Args: subtoken_counts: defaultdict mapping subtokens to their counts min_count: int count used to filter subtokens Returns: List of subtoken sets, where subtokens in set i have the same length=i. """

  # Create list of buckets, where subtokens in bucket i have length i.
  subtoken_buckets = []
  for subtoken, count in six.iteritems(subtoken_counts):
    if count < min_count:  # Filter out subtokens that don't appear enough
      continue
    while len(subtoken_buckets) <= len(subtoken):
      subtoken_buckets.append(set())
    subtoken_buckets[len(subtoken)].add(subtoken)
  return subtoken_buckets