code: def _make_ctf_name(directory, extra, raise_error=True):
      """Make a CTF name."""
      fname = op.join(
          directory, op.basename(directory)[:-3] + "." + extra
      )
      found = True
      if not op.isfile(fname):
          if raise_error:
              raise OSError("Standard file %s not found" % fname)
          found = False
      return fname, found
  
file_path: mne-python/mne/io/ctf/res4.py
imports: import os.path
  import numpy
  from ...utils import logger
  from .constants import CTF
label_desc: Use image node_id 1 for calling a global function with example usage: _make_ctf_name(directory, extra, raise_error) and returns: fname,  found