Python: count repeated elements in the list

You can do that using count:

my_dict = {i:MyList.count(i) for i in MyList}

>>> print my_dict     #or print(my_dict) in python-3.x
{a: 3, c: 3, b: 1}

from collections import Counter

a = dict(Counter(MyList))

>>> print a           #or print(a) in python-3.x
{a: 3, c: 3, b: 1}

Use Counter

>>> from collections import Counter
>>> MyList = [a, b, a, c, c, a, c]
>>> c = Counter(MyList)
>>> c
Counter({a: 3, c: 3, b: 1})

This works for Python 2.6.6

a = [a, b, a]
result = dict((i, a.count(i)) for i in a)
print result

prints

{a: 2, b: 1}