merge dictionaries python code example

Example 1: join two dictionaries python

z = {**x, **y}

Example 2: python join dict

dict.update([other])

Example 3: merge two dict python 3

z = {**x, **y}

Example 4: python merge dictionaries

dict1 = {'color': 'blue', 'shape': 'square'}
dict2 = {'color': 'red', 'edges': 4}

dict1.update(dict2) #if a key exists in both, it takes the value of the second dict
# dict1 = {'color': 'red', 'shape': 'square', 'edges': 4}
# dict2 is left unchanged

Example 5: how to merge a list of dictionaries in python

from collections import defaultdict
dict_list = {
	1: [{
			"x": "test_1",
			"y": 1
		},
		{
			"x": "test_2",
			"y": 1
		}, {
			"x": "test_1",
			"y": 2
		}
	],
}
print(dict_list) # {1: [{'x': 'test_1', 'y': 1}, {'x': 'test_2', 'y': 1}, {'x': 'test_1', 'y': 2}]}

data = dict()
for key, value in dict_list.items():
    tmp = defaultdict(int)
    for index, item in enumerate(value):
        tmp[item.get("x") ] += item.get("y")

    for tmp_key, tmp_value in tmp.items():
        data.setdefault(key, []).append(
            {
                "x": tmp_key,
                "y": tmp_value
            }
        )
print(data) # {1: [{'x': 'test_1', 'y': 3}, {'x': 'test_2', 'y': 1}]}

# test 1 values is added together

Example 6: concatenate two dictionnaries python

d1.update(d2)