gistfile1.py

def is_in(val, list):
    for item in list:
        if item == val:
            return True
    return False

print is_in(1, [1, 2, 3]) # True
print is_in(5, [1, 2, 3]) # False

if is_in('r', ['r', 'R', 'rand', 'random', 'Rand', 'Random']):
    print "It's random baby!!"