input: Write a python function to generate a grid-like pattern of user input values.
  assert generate_grid([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12], [13, 14, 15]]) == "1\t\t2\t\t3\t\t\n4\t\t5\t\t6\t\t\n7\t\t8\t\t9\t\t\n10\t\t11\t\t12\t\t\n13\t\t14\t\t15\t\t\n"
  assert generate_grid([['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i'], ['j', 'k', 'l'], ['m', 'n', 'o']]) == "a\t\tb\t\tc\t\t\nd\t\te\t\tf\t\t\ng\t\th\t\ti\t\t\nj\t\tk\t\tl\t\t\nm\t\tn\t\to\t\t\n"
output: def generate_grid(values):
      return '\n'.join(['\t\t'.join(map(str, row)) + '\t\t' for row in values]) + '\n'