Anay and Polynomial

Let $P$ be a polynomial in $n$ variables given by: $$ P(x_1, x_2, \ldots,x_{n}) = (k + x_1 + x_2 + \cdots + x_{n})^{m} $$ Here $n$, $k$ and $m$ are positive integers. Find the sum of all coefficients of the terms of the polynomial which have even powers in each of the $n$ variables and output it modulo $10^9 + 7$. Note that the constant term's coefficient is also included in the sum. Pl