Hi! I'm having trouble with this code (Python):
*Basically Im trying to ask if you have a sibling or not and if you don't then it will like not give you questions and if you do it will give you questions*

sd = input('Do you have a sibling? Answer 1 for yes or 2 for no please.')
if sd = 2:
print('Cool - you are a only child!')
else:
num1 = input('How old is your sibling?')
num2 = input('How old are you?')


if num1 > num2:
print('Your sibling is younger than you!')
elif num1 < num2:
print('You are older than your sibling!')
else:
print('You and your sibling are most likely born in the same year / twins!')

The thing is its saying that this line:
if sd = 2:

Its saying it has an error. I don't know whats going on I tried everything!! Please help it would mean a lot to a seventh grader who has started learning Python two weeks ago and with Asian parents with very high expectations . Thank you once again!