  In this note, we give the explicit formula for the number of multisubsets of
a finite abelian group $G$ with any given size such that the sum is equal to a
given element $g\in G$. This also gives the number of partitions of $g$ into a
given number of parts over a finite abelian group. An inclusion-exclusion
formula for the number of multisubsets of a subset of $G$ with a given size and
a given sum is also obtained.
