The sum of combination $ \sum _{i \equiv q \pmod p} {n \choose i}$

Question

Let $p$ be natural number such that $p \geq 2$. And $q$ is natural number such that $ 0 \leq q \leq p-1 $.
What is $ \sum _{i \equiv q \pmod p} {n \choose i}$? I solved it for $p=2, 3, 4, 5, 7$, but I cannot generalize it. I solved it by using complex number $w$ such that $w^p=1$ and Binomial theorem. Is there better ways?