python - Compare groups of 4 characters to see if they're the same in a string -

i'm trying use python compare 2 strings , see if of them have common groups of 4 letters.

sequence1 = "acacgcgtctccttgcgggtaaat" sequence2 = "gttaccaatttcttgtttccgaat"  in range(0,24,4):     print     list1.append(sequence1[i:i+4])  in range(0,24,4):     print     list2.append(sequence2[i:i+4]) 

but doesn't seem it. want return groups of letters equal in both strings, ideas?

you can iterate on groups of 4 using list comprehension slicing. have edited sequences contain 2 common 4 letter elements:

s1 = "acacgcggtctcttgcgggaaatt" s2 = "gttaccaatttcttgcttccaaat"  c = [s1[i:i+4] in range(0, len(s1), 4) if s1[i:i+4] in s2] 

the list c contains common entries: ['ttgc', 'aaat']

do note, not discriminate on position; if required change if statement in list comprehension define that:

c = [s1[i:i+4] in range(0, len(s1), 4) if s1[i:i+4] == s2[i:i+4]] 

now contains ['ttgc'].