input: Write a function that takes in two strings and outputs their combined length.
  
  def get_string_length(string_1, string_2):
      return len(string_1 + string_2)
  
  assert get_string_length("Hello", "World")==10
  assert get_string_length("Python", "Programming")==17
  assert get_string_length("", "Code")==4
  assert get_string_length("Test", "")==4
  assert get_string_length("", "")==0
output: def get_string_length(string_1, string_2):
      return len(string_1 + string_2)