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pythonpython-itertools

Flatten product of two dictionary lists

I have two lists of dictionaries which I am trying to get the product of:

from itertools import product 


list1 = [{'A': 1, 'B': 1}, {'A': 2, 'B': 2}, {'A': 2, 'B': 1}, {'A': 1, 'B': 2}]
list2 = [{'C': 1, 'D': 1}, {'C': 1, 'D': 2}]

for p in product(list1, list2):
    print p

and this gives me the output:

({'A': 1, 'B': 1}, {'C': 1, 'D': 1})
({'A': 1, 'B': 1}, {'C': 1, 'D': 2})
({'A': 2, 'B': 2}, {'C': 1, 'D': 1})
({'A': 2, 'B': 2}, {'C': 1, 'D': 2})
({'A': 2, 'B': 1}, {'C': 1, 'D': 1})
({'A': 2, 'B': 1}, {'C': 1, 'D': 2})
({'A': 1, 'B': 2}, {'C': 1, 'D': 1})
({'A': 1, 'B': 2}, {'C': 1, 'D': 2})

How would I flatten these so the output is a single dict rather than a tuple of dicts?:

{'A': 1, 'B': 1, 'C': 1, 'D': 1}
{'A': 1, 'B': 1, 'C': 1, 'D': 2}
{'A': 2, 'B': 2, 'C': 1, 'D': 1}
{'A': 2, 'B': 2, 'C': 1, 'D': 2}
{'A': 2, 'B': 1, 'C': 1, 'D': 1}
{'A': 2, 'B': 1, 'C': 1, 'D': 2}
{'A': 1, 'B': 2, 'C': 1, 'D': 1}
{'A': 1, 'B': 2, 'C': 1, 'D': 2}
Solution

  • Looks like you want to merge the dictionaries

     for p1, p2 in product(list1, list2):
     merged = {**p1, **p2}
     print(merged)

    In earlier versions of Python, you can't merge with this expression. Use p1.update(p2) instead.