python dict list value join each with key code example

Example 1: join two dictionaries python

z = {**x, **y}

Example 2: merge a list of dictionaries python

>>> from collections import ChainMap
>>> a = [{'a':1},{'b':2},{'c':1},{'d':2}]
>>> dict(ChainMap(*a))
{'b': 2, 'c': 1, 'a': 1, 'd': 2}

Example 3: python join dict

def mergeDict(dict1, dict2):
   ''' Merge dictionaries and keep values of common keys in list'''
   dict3 = {**dict1, **dict2}
   for key, value in dict3.items():
       if key in dict1 and key in dict2:
               dict3[key] = [value , dict1[key]]
 
   return dict3
 
# Merge dictionaries and add values of common keys in a list
dict3 = mergeDict(dict1, dict2)
 
print('Dictionary 3 :')
print(dict3)