Use Collection module counter function to sum dictionary values by key in Python. The counter is a sub-class that is used to count hashable objects and count each of the elements present in the container.
Example sum dictionary values by key in Python
Simple example code has two dictionaries with the same keys and different numeric values. We are merging these dictionaries into one and sum the dictionary values by key.
from collections import Counter
x = {"a": 200, "b": 560, "y": 2005, "z": 2555}
y = {"a": 255, "b": 266, "y": 3050, "z": 3033}
z = Counter(x) + Counter(y)
print(z)
Output:

For example, if you want to add all the values of a dictionary together to find the sum. Call dict.values() to return the values of a dictionary dict then use sum(values) to return the sum of the values.
a_dict = {"a": 1, "b": 2, "c": 3}
values = a_dict.values()
total = sum(values)
print(total)
Output: 6
Do comment if you have any doubts or suggestions on this Python sum topic.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.

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