code: def loc_block(self, name: Union[str, List[str]], with_offset=True):
      if isinstance(name, str):
          field_index = self._schema_manager.get_field_offset(name)
          return self._block_manager.loc_block(field_index, with_offset)
      else:
          loc_ret = []
          for _name in name:
              field_index = self._schema_manager.get_field_offset(_name)
              loc_ret.append(
                  self._block_manager.loc_block(
                      field_index, with_offset
                  )
              )
  
          return loc_ret
  
imports: import numpy
  from .schema_manager import SchemaManager
  from .block_manager import BlockManager
  from .block_manager import BlockType
  import pandas
  from ..entity import types
  from typing import Union, List, Tuple
  from ..conf.default_config import DATAFRAME_BLOCK_ROW_SIZE
label_desc: Use image node_id 15 for calling the DataManager obj's underlying member method code with example usage: obj.loc_block(name, with_offset) and returns: self, loc_ret