old_contents: # encoding: utf-8
  
  """
  .. codeauthor:: Tsuyoshi Hombashi <gogogo.vm@gmail.com>
  """
  
  from __future__ import absolute_import
  
  import dataproperty
  
  from ..data import TableData
  from ..error import InvalidDataError
  from ..formatter import TableFormatter
  
  
  class CsvTableFormatter(TableFormatter):
  
      def to_table_data(self):
          if dataproperty.is_empty_sequence(self._loader.header_list):
              header_list = self._source_data[0]
  
              if any([
                  dataproperty.is_empty_string(header) for header in header_list
              ]):
                  raise InvalidDataError(
                      "the first line includes empty string item: "
                      "the first line expected to contain header data.")
  
              data_matrix = self._source_data[1:]
          else:
              header_list = self._loader.header_list
              data_matrix = self._source_data
  
          if len(data_matrix) == 0:
              raise InvalidDataError(
                  "data row must be greater or equal than one")
  
          self._loader.inc_table_count()
  
          yield TableData(
              self._loader.make_table_name(),
              header_list, data_matrix)
  
new_contents: # encoding: utf-8
  
  """
  .. codeauthor:: Tsuyoshi Hombashi <gogogo.vm@gmail.com>
  """
  
  from __future__ import absolute_import
  
  import dataproperty
  
  from ..data import TableData
  from ..error import InvalidDataError
  from ..formatter import TableFormatter
  
  
  class CsvTableFormatter(TableFormatter):
  
      def to_table_data(self):
          if dataproperty.is_empty_sequence(self._loader.header_list):
              header_list = self._source_data[0]
  
              if any([
                  dataproperty.is_empty_string(header) for header in header_list
              ]):
                  raise InvalidDataError(
                      "the first line includes empty string item."
                      "all of the items should contain header name."
                      "actual={}".format(header_list))
  
              data_matrix = self._source_data[1:]
          else:
              header_list = self._loader.header_list
              data_matrix = self._source_data
  
          if len(data_matrix) == 0:
              raise InvalidDataError(
                  "data row must be greater or equal than one")
  
          self._loader.inc_table_count()
  
          yield TableData(
              self._loader.make_table_name(),
              header_list, data_matrix)
  
subject: Modify error message