Independent variable if I’m not mistaken
        
             
        
        
        
Jude be done. Die he ehe ehehevehe Ed
        
             
        
        
        
Answer:
# string_contains function is defined with input_string
# as arguments
def string_contains(input_string):
    # if-statement that check if letter z is in input_string
    if 'z' in input_string:
        # it print"has the letter z" if it has z
        print("has the letter z")
    else:
        # else it print "not worthwhile"
        print("not worthwhile")
        
# string_contains function is called
string_contains("The animal is zebra")        
string_contains("learning is fun")
Explanation:
The code is written in Python and well commented.
Image of the output when the function is called is attached.