How??

Question

Let dit={1:'a',3:'b',2:'c'}
Now if I use print(dit[1])
I get 'a', But what if I want to enter the value 'b' and get 3.

Answer 1

The keys in a dictionary are unique, but the values don't have to be. So you can have in the same dictionary also 4:'b' and 77:'b'
For this reason there is no straightforward answer but you can find a few ways how to solve this, here:
https://www.google.com/amp/s/www.geeksforgeeks.org/JUMP_LINK__&&__python__&&__JUMP_LINK-get-key-from-value-in-dictionary/amp/