code: def pdbqt_to_pdb(
      filename: Optional[str] = None,
      pdbqt_data: Optional[List[str]] = None,
  ) -> str:
      """Extracts the PDB part of a pdbqt file as a string.
  
      Either `filename` or `pdbqt_data` must be provided. This function
      strips PDBQT charge information from the provided input.
  
      Parameters
      ----------
      filename: str, optional  (default None)
          Filename of PDBQT file
      pdbqt_data: List[str], optional (default None)
          Raw list of lines containing data from PDBQT file.
  
      Returns
      -------
      pdb_block: str
          String containing the PDB portion of pdbqt file.
      """
      if filename is not None and pdbqt_data is not None:
          raise ValueError(
              "Only one of filename or pdbqt_data can be provided"
          )
      elif filename is None and pdbqt_data is None:
          raise ValueError(
              "Either filename or pdbqt_data must be provided"
          )
      elif filename is not None:
          pdbqt_data = open(filename).readlines()
  
      pdb_block = ""
      # FIXME: Item "None" of "Optional[List[str]]" has no attribute "__iter__" (not iterable)
      for line in pdbqt_data:  # type: ignore
          pdb_block += "%s\n" % line[:66]
      return pdb_block
  
file_path: deepchem/deepchem/utils/pdbqt_utils.py
imports: from typing import Dict, List, Optional, Set, Tuple
  from deepchem.utils.typing import RDKitMol
label_desc: Use image node_id 1 for calling a global function with example usage: pdbqt_to_pdb(filename, pdbqt_data) and returns: pdb_block