Generate a Python code snippet to search for a specific value in a 2D list and return its index.
Value to search for: "hello"
2D List: [[12, "goodbye", 21], ["hello", 67, 55]]
def search_2d(value, lst):
 for i, row in enumerate(lst):
  if value in row:
   return (i, row.index(value))

print(search_2d("hello", [[12, "goodbye", 21], ["hello", 67, 55]]))
# Output: (1, 0)