docs: def get_module(mod_name):
      """
      Load and return a module based on C{mod_name}.
      """
      if mod_name is '':
          raise ImportError('Unable to import empty module')
  
      mod = __import__(mod_name)
      components = mod_name.split('.')
  
      for comp in components[1:]:
          mod = getattr(mod, comp)
  
      return mod