output_description: Print the number of ways modulo $10^9+7$ in a line.
input_description: $n$ $k$
      
  
  The first line will contain two integers $n$ and $k$.
attempt: N, K = map(int, input().split())
  MOD = 10**9 + 7
  
  if K < N:
      print(0)
  else:
      p = q = 1
      for i in range(N):
          p = p * (K - i) % MOD
          q = q * (i + 1) % MOD
  
      print(p * pow(q, MOD - 2, MOD) % MOD)
  
problem_description: You have $n$ balls and $k$ boxes. You want to put these balls into the boxes.
  
  Find the number of ways to put the balls under the following conditions:
  
    * Each ball is **not** distinguished from the other.
    * Each box is distinguished from the other.
    * Each ball can go into only one box and no one remains outside of the boxes.
    * Each box can contain at most one ball.
  
  Note that you must print this count modulo $10^9+7$.
samples: [{"input": "3 5", "output": "10"}, {"input": "5 10", "output": "252"}, {"input": "100 200", "output": "407336795"}]