Write a python function to find the minimum of two numbers.
def minimum(a,b):   
    if a <= b: 
        return a 
    else: 
        return b 
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a python function to find the minimum of two numbers.
def minimum(a,b):   
    if a <= b: 
        return a 
    else: 
        return b [/INST]assert minimum(1,2) == 1
assert minimum(-5,-4) == -5
assert minimum(0,0) == 0</s>