docs: def _images(self, sys_output):
      
          ''' a helper method for parsing docker image output '''
  
          import re
          gap_pattern = re.compile('\t|\s{2,}')
          image_list = []
          output_lines = sys_output.split('\n')
          column_headers = gap_pattern.split(output_lines[0])
          for i in range(1,len(output_lines)):
              columns = gap_pattern.split(output_lines[i])
              if len(columns) == len(column_headers):
                  image_details = {}
                  for j in range(len(columns)):
                      image_details[column_headers[j]] = columns[j]
                  image_list.append(image_details)
  
          return image_list