The following code could be rewritten into a single if statement that checks for either condition to be true using:

if (x > 12):
if (x < 34):
a) if (x > 12) or (x < 34):
b) if (x > 12) and (x < 34):
c) if (x > 12) | (x < 34):
d) if (x > 12) & (x < 34):