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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 _StructPackEncoder(wire_type, format):
 """Return a constructor for an encoder for a fixed-width field. Args: wire_type: The field's wire type, for encoding tags. format: The format string to pass to struct.pack(). """


  value_size = struct.calcsize(format)

  def SpecificEncoder(field_number, is_repeated, is_packed):
    local_struct_pack = struct.pack
    if is_packed:
      tag_bytes = TagBytes(field_number, wire_format.WIRETYPE_LENGTH_DELIMITED)
      local_EncodeVarint = _EncodeVarint
      def EncodePackedField(write, value):
        write(tag_bytes)
        local_EncodeVarint(write, len(value) * value_size)
        for element in value:
          write(local_struct_pack(format, element))
      return EncodePackedField
    elif is_repeated:
      tag_bytes = TagBytes(field_number, wire_type)
      def EncodeRepeatedField(write, value):
        for element in value:
          write(tag_bytes)
          write(local_struct_pack(format, element))
      return EncodeRepeatedField
    else:
      tag_bytes = TagBytes(field_number, wire_type)
      def EncodeField(write, value):
        write(tag_bytes)
        return write(local_struct_pack(format, value))
      return EncodeField

  return SpecificEncoder