Create a function in Python that takes two arrays as arguments and returns a new array that contains the elements of both arguments.
arr_1 = [1, 2, 3];
arr_2 = [4, 5, 6];
def merge_arrays(arr_1, arr_2):
  return arr_1 + arr_2
  
result = merge_arrays(arr_1, arr_2)
print(result) #[1, 2, 3, 4, 5, 6]