code: def _read_faces(
      file, n_faces: int
  ) -> Tuple[Optional[np.ndarray], Optional[np.ndarray]]:
      """
      Returns faces and face colors from the file.
  
      Args:
          file: file-like object being read.
          n_faces: The known number of faces.
  
      Returns:
          2D numpy arrays of faces and face colors, or None for each if
              they are not present.
      """
      if n_faces == 0:
          return None, None
  
      color_is_int = 0 == _count_next_line_periods(file)
      color_scale = 1 / 255.0 if color_is_int else 1
  
      faces_ncolors_colors = _read_faces_lump(
          file, n_faces=n_faces, n_colors=None
      )
      if faces_ncolors_colors is not None:
          faces, _, colors = faces_ncolors_colors
          if colors is None:
              return faces, None
          return faces, colors * color_scale
  
      faces_list, colors_list = [], []
      n_colors = None
      for _ in range(n_faces):
          faces_ncolors_colors = _read_faces_lump(
              file, n_faces=1, n_colors=n_colors
          )
          faces_found, n_colors, colors_found = cast(
              Tuple[np.ndarray, int, Optional[np.ndarray]],
              faces_ncolors_colors,
          )
          faces_list.append(faces_found)
          colors_list.append(colors_found)
      faces = np.vstack(faces_list)
      if n_colors == 0:
          colors = None
      else:
          colors = np.vstack(colors_list) * color_scale
      return faces, colors
  
imports: import warnings
  from typing import cast, Optional, Tuple, Union
  import numpy
  import torch
  from iopath.common.file_io import PathManager
  from pytorch3d.io.utils import _check_faces_indices, _open_file, PathOrStr
  from pytorch3d.renderer import TexturesAtlas, TexturesVertex
  from pytorch3d.structures import Meshes
  from .pluggable_formats import endswith, MeshFormatInterpreter
label_desc: Use image node_id 4 for calling a global function with example usage: _read_faces(file, n_faces) and returns: faces,  colors, None,  None, faces,  unknown, faces,  None