Align strings over a common character

I am looking for a simple, pythonic way of doing this with the minimum calculations and loops.

I have a bunch of strings, such as:

1 + 2 = 3

2*6 + 13 = 25

What I would like to print at the screen is:

xxx1 + 2 = 3

2*6 + 13 = 25

(where the x are actually spaces, but I could not figure out how to show it with this editor)

I am aware of string formatting with left and right align but this imply for each string to compute the number of spaces to add, convert it into a string, and inject this into the string alignment formatter, which seems complex.

Is there a simpler way?

Answer

Based on the information you provided, this may work:

lst = [
'1 + 2 = 3',
'2*6 + 13 = 25',
'2*6 = 12',
'2 = 12 - 10'
]

mxleft = max([e.index('=') for e in lst])

l2 = [e.split('=')[0].rjust(mxleft) + '=' + e.split('=')[1] for e in lst]

print('n'.join(l2))

Output

   1 + 2 = 3
2*6 + 13 = 25
     2*6 = 12
       2 = 12 - 10