def AA(n):
    """constructs the AA context"""
    if (n<=1):return Context('10\n00')
    else:
        AA1=AA(n-1)
        r1 = C1(2**(n-1),2**(n-1)) - AA1
        r2 = AA1 - AA1
        return r1 + r2
def AA ( n ) : if ( n <= 1 ) : return Context ( '10\n00' ) else : AA1 = AA ( n - 1 ) r1 = C1 ( 2 ** ( n - 1 ) , 2 ** ( n - 1 ) ) - AA1 r2 = AA1 - AA1 return r1 + r2
constructs the AA context