Merge

Merge[{assoc1,assoc2,…},f] merges the associations associ, using the function f to combine values with the same key. 

Merge[{key1->val1,key2->val2,…},f] gives an association in which values corresponding to identical keys are combined using f. 

Merge[f] represents an operator form of Merge that can be applied to an expression.

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