code: def read_str(self, char_count, base, offset=0):
          
          def str_struct(char_count):
              format_ = '%ds' % char_count
              return Struct(format_)
          struct = str_struct(char_count)
          chars = self._unpack_item(struct, base, offset)
          unicode_str = chars.decode('UTF-8')
          return unicode_str
docs: Return a string containing the *char_count* bytes at the file
          position determined by self._base_offset + *base* + *offset*.