
Surjection Strings
Maybe it's a cipher? Maybe, but we don’t know for sure.
Maybe you can call it "homomorphism"? I wish I knew this word before.
You need to check that the string A is isometric to the string B. There exists a function that turns characters from A into characters in the same spot in B.
Characters in A correspond to a unique character value in B. Characters in B are allowed to correspond to multiple character values in A.

Input: Two strings (str).
Output: Logic value (bool).
Examples:
assert isometric_strings("add", "egg") == True assert isometric_strings("foo", "bar") == False assert isometric_strings("bar", "foo") == True assert isometric_strings("", "") == True
Precondition:
- both strings have the same length.