python collections OrderedDict

from collections import namedtuple
from collections import OrderedDict, defaultdict

# count no elements
# print dict in same order
d = OrderedDict() 
n = 5
ll = ['aaa', 'bbb', 'ccc', 'aaa']
for i in ll:
    d.setdefault(i, 0)  #it initialises to, else index error may come first time 
    d[i]+= 1

print(len(d))            # 3 
print(*d.values())   # 2 1 1
print(d)              #OrderedDict([('aaa', 2), ('bbb', 1), ('ccc', 1)])