code: def load_from_file(self, filename=None, *, strict=True):
          
          self.set_to_default()
  
          if filename:
              self._update_from_file(filename)
          else:
              if LIGHTFLOW_CONFIG_ENV not in os.environ:
                  if os.path.isfile(os.path.join(os.getcwd(), LIGHTFLOW_CONFIG_NAME)):
                      self._update_from_file(
                          os.path.join(os.getcwd(), LIGHTFLOW_CONFIG_NAME))
                  elif os.path.isfile(expand_env_var('~/{}'.format(LIGHTFLOW_CONFIG_NAME))):
                      self._update_from_file(
                          expand_env_var('~/{}'.format(LIGHTFLOW_CONFIG_NAME)))
                  else:
                      if strict:
                          raise ConfigLoadError('Could not find the configuration file.')
              else:
                  self._update_from_file(expand_env_var(os.environ[LIGHTFLOW_CONFIG_ENV]))
  
          self._update_python_paths()
docs: Load the configuration from a file.
  
          The location of the configuration file can either be specified directly in the
          parameter filename or is searched for in the following order:
  
              1. In the environment variable given by LIGHTFLOW_CONFIG_ENV
              2. In the current execution directory
              3. In the user's home directory
  
          Args:
              filename (str): The location and name of the configuration file.
              strict (bool): If true raises a ConfigLoadError when the configuration
                  cannot be found.
  
          Raises:
              ConfigLoadError: If the configuration cannot be found.