code: def get_named_arg(name, default_val=None, reqd=False):
      
      if name in sys.argv:  # if the command line flag is found in sys.argv
          ind = sys.argv.index(name)
          return sys.argv[ind + 1]
      if reqd:  # if arg is required but not present
          raise MissingCommandLineArgException(name)
      return default_val
docs: Extract the value after a command-line flag such as '-f' and return it.
      If the command-line flag is missing, return default_val.
      If reqd == True and the command-line flag is missing, throw an error.
  
      Parameters
      ----------
      name : str
          command line flag, e.g. "-f"
      default_val
          value to use if command line flag is missing, e.g. "measurements.txt"
          default is None
      reqd : bool
          throw error if reqd==True and command line flag is missing.
          if reqd == True, default_val will be ignored.
          default is False.
  
      Returns
      ---------
      Desired value from sys.argv if available, otherwise default_val.