How merge a dict and a list and adding more value to it?

Question

we have this dict and this list

mydict={a:1,b:1}
mylist=[a,b,a,c]

I want to merge that list into the dict like this:

mydict={a:3,b:2,c:1}

Answer 1

A companion to @meTchaikovsky's answer.

for item in mylist:
    mydict[item] = mydict.get(item, 0) + 1