The program below calculates the conditional entropy of the conditional distribution of seq$2$ given seq$1.$

seq$1=[\text{'}$apple$\text{'},$ 'pear', 'lemon', 'lemon'$]$

seq$2=[$True$,$ False, True, True$]$

cd $=$ conditionally$\_$distribute$($seq$1,$ seq$2)$

print$($conditional$\_$entropy$($distribute$($seq$1),$ cd$))$

The output of the program is zero because: