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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 BytesSizer(field_number, is_repeated, is_packed):
 """Returns a sizer for a bytes field."""


  tag_size = _TagSize(field_number)
  local_VarintSize = _VarintSize
  local_len = len
  assert not is_packed
  if is_repeated:
    def RepeatedFieldSize(value):
      result = tag_size * len(value)
      for element in value:
        l = local_len(element)
        result += local_VarintSize(l) + l
      return result
    return RepeatedFieldSize
  else:
    def FieldSize(value):
      l = local_len(value)
      return tag_size + local_VarintSize(l) + l
    return FieldSize