input: Write a function that determines the sum of the digits in a given number N and then converts this sum into its binary representation.
  assert solve(1000) == "1"
  assert solve(150) == "110"
  assert solve(147) == "1100"
  assert solve(333) == "1001"
  assert solve(963) == "10010"
output: def solve(N):
      return bin(sum(int(d) for d in str(N)))[2:]