Replace the priority column ('yes'/'no') with boolean values (True/False) and return the DataFrame.

Input

  animal  age  visits priority
a    cat  2.5       1      yes
b    cat  3.0       3      yes
c  snake  0.5       2       no
d    dog  NaN       3      yes
e    dog  5.0       2       no
f    cat  2.0       3       no
g  snake  4.5       1       no
h    cat  NaN       1      yes
i    dog  7.0       2       no
j    dog  3.0       1       no

Output

  animal  age  visits  priority
a    cat  2.5       1      True
b    cat  3.0       3      True
c  snake  0.5       2     False
d    dog  NaN       3      True
e    dog  5.0       2     False
f    cat  2.0       3     False
g  snake  4.5       1     False
h    cat  NaN       1      True
i    dog  7.0       2     False
j    dog  3.0       1     False