code: def get_length_from_varchar(x):
      """Retrieve the length of a varchar column from its coltype def"""
      m = re.match(r"^varchar\(([0-9]+)\)$", x)
      if m is None:
          return None
      return int(m.groups()[0])
  
file_path: CellProfiler/src/subpackages/core/cellprofiler_core/utilities/measurement.py
imports: import os
  import re
  import sys
  import tempfile
  from .hdf5_dict import get_top_level_group
  from .hdf5_dict import VERSION
label_desc: Use image node_id 1 for calling a global function with example usage: get_length_from_varchar(x) and returns: int, None