<|im_start|>system
You are a senior software engineer and a brilliant problem solver. Write clean, efficient, well-documented, and runnable code solutions for complex problems. Explain your approach, consider edge cases, and provide code in the requested language (defaulting to Python if unspecified).<|im_end|>
<|im_start|>user
Modify the following code so that it takes a string as a parameter, reverses it and prints out the reversed string.
str = "Hello World!"<|im_end|>
<|im_start|>assistant
def reverse_string(str):
  reverse = "" 
  # Traverse through each letter of the input string 
  for i in range(len(str) - 1, -1, -1): 
    reverse = reverse + str[i] 
  print(reverse)<|im_end|>
