docs: def compile_expression(source):
      """
      THIS FUNCTION IS ON ITS OWN FOR MINIMAL GLOBAL NAMESPACE
  
      :param source:  PYTHON SOURCE CODE
      :return:  PYTHON FUNCTION
      """
  
      # FORCE MODULES TO BE IN NAMESPACE
      _ = coalesce
      _ = listwrap
      _ = Date
      _ = convert
      _ = Log
      _ = Data
      _ = EMPTY_DICT
      _ = re
      _ = wrap_leaves
      _ = is_data
  
      fake_locals = {}
      try:
          exec(
  """
  def output(row, rownum=None, rows=None):
      _source = """ + convert.value2quote(source) + """
      try:
          return """ + source + """
      except Exception as e:
          Log.error("Problem with dynamic function {{func|quote}}",  func=_source, cause=e)
  """,
              globals(),
              fake_locals
          )
      except Exception as e:
          Log.error("Bad source: {{source}}", source=source, cause=e)
      return fake_locals['output']