input: Write a python function to find the maximum product of digits in a list of numbers.
  assert find_max([123, 456, 789]) == 504
  assert find_max([12, 34, 56, 78]) == 336
  assert find_max([111, 222, 333]) == 27
output: def find_max(numbers):
      def product_of_digits(n):
          product = 1
          while n > 0:
              product *= n % 10
              n //= 10
          return product
      
      return max(product_of_digits(num) for num in numbers)