Write a python function to find the most significant bit number which is also a set bit.
def set_Bit_Number(n): 
    if (n == 0): 
        return 0; 
    msb = 0; 
    n = int(n / 2); 
    while (n > 0): 
        n = int(n / 2); 
        msb += 1; 
    return (1 << msb)
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a python function to find the most significant bit number which is also a set bit.
def set_Bit_Number(n): 
    if (n == 0): 
        return 0; 
    msb = 0; 
    n = int(n / 2); 
    while (n > 0): 
        n = int(n / 2); 
        msb += 1; 
    return (1 << msb)[/INST]assert set_Bit_Number(6) == 4
assert set_Bit_Number(10) == 8
assert set_Bit_Number(18) == 16</s>