string formatting

[Uchikago]

Hi, i want to ask that when using string formatting:

>>> b={1:'a','1':'c'}
>>> print('%(1)s abcd' % b)
c abcd

How can we refer to the keys 1 (has value 'a') not the key '1' (has 'c' value).
Thank you very much!

[buran]

>> print('some {spam}'.format(**foo))
some a
>>> print(f'some {foo["eggs"]}')
some b