count number of ocurrences of each key in python dict code example

Example 1: get number of key in dictionary python

#Call len(obj) with a dictionary as obj to count the number 
#of key-value pairs in the dictionary.

a_dictionary = {"a": 1, "b": 2}
print(len(a_dictionary))

OUTPUT:
2

Example 2: python counting dictionary

counts = dict()
for i in items:
  counts[i] = counts.get(i, 0) + 1