Getting named parameters from Python string [duplicate]

Question

I am trying to get a list of parameters from a formatted Python string.

So my string looks something like this:

formatted_string = 'I am {foo}. You are {{my}} {bar}.'

I am trying do to something like:

get_named_parameters(formatted_string) = ['foo', 'bar']

Is there a way of doing that without making my own function? I couldn't find anything in String Formatter docs.

I am using Python3, but it would be nice if it would work in 2.7 as well.

Answer 1

Using string.Formatter.parse:

In [7]: from string import Formatter

In [8]: [x[1] for x in Formatter().parse(formatted_string) if x[1] is not None]
Out[8]: ['foo', 'bar']