1  import inspect
 2  
 3  
 4  def _get_arg_names(f):
 5      """Get the argument names of a function.
 6  
 7      Args:
 8          f: A function.
 9  
10      Returns:
11          A list of argument names.
12  
13      """
14      # `inspect.getargspec` or `inspect.getfullargspec` doesn't work properly for a wrapped function.
15      # See https://hynek.me/articles/decorators#mangled-signatures for details.
16      return list(inspect.signature(f).parameters.keys())