docs: def setup(cls, ikpdb_log_arg):
          """ activates DEBUG logging level based on the `ikpdb_log_arg` 
          parameter string.
          
          `ikpdb_log_arg` corresponds to the `--ikpdb-log` command line argument.
             
          `ikpdb_log_arg` is composed of a serie of letters that set the `DEBUG` 
          logging level on the components of the debugger.
             
          Here are the letters and the component they activate `DEBUG` logging 
          level on:
          
              - n,N: Network 
              - b,B: Breakpoints 
              - e,E: Expression evaluation
              - x,X: Execution 
              - f,F: Frame 
              - p,P: Path and python path manipulation
              - g,G: Global debugger
          
          By default logging is disabled for all components. 
          Any `ikpdb_log_arg` value different from the letters above (eg: '9') 
          activates `INFO`  level logging on all domains.
          
          To log, use::
          
              _logger.x_debug("useful information")
      
          Where:
              - `_logger` is a reference to the IKPdbLogger class
              - `x` is the `Execution` domain
              - `debug` is the logging level
          """
          if not ikpdb_log_arg:
              return
          
          IKPdbLogger.enabled = True
          logging_configuration_string = ikpdb_log_arg.lower()
          for letter in logging_configuration_string:
              if letter in IKPdbLogger.DOMAINS:
                  IKPdbLogger.DOMAINS[letter] = 10