import string
data = {x: [] for x in range(5)}
letters = list(string.ascii_lowercase[:3]) # ['a','b','c']
for i in data:
data[i].extend(letters)
for key, value in data.items():
print(key, ":", value)
'''
run:
0 : ['a', 'b', 'c']
1 : ['a', 'b', 'c']
2 : ['a', 'b', 'c']
3 : ['a', 'b', 'c']
4 : ['a', 'b', 'c']
'''