code: def validate_grid_path(r, c, s, t, p):
      assert isinstance(p, list)
      assert p[0] == s
      assert p[-1] == t
      s = ((s - 1) // c, (s - 1) % c)
      t = ((t - 1) // c, (t - 1) % c)
      assert len(p) == abs(t[0] - s[0]) + abs(t[1] - s[1]) + 1
      p = [((u - 1) // c, (u - 1) % c) for u in p]
      for u in p:
          assert 0 <= u[0] < r
          assert 0 <= u[1] < c
      for u, v in zip(p[:-1], p[1:]):
          assert (abs(v[0] - u[0]), abs(v[1] - u[1])) in [
              (0, 1),
              (1, 0),
          ]
  
imports: import pytest
  import networkx
label_desc: Use image node_id 1 for calling a global function with example usage: validate_grid_path(r, c, s, t, p) without return types