Question

python的list16. all_pairs(xs,ys). Create and return a list of

Answer 1

16.

def all_pairs(xs,ys):

xy_list=[]

for x in xs:

for y in ys:

xy=(x,y)

xy_list.append(xy)

return(xy_list)

all_pairs([1,2,3], ['a','b'])

17.

def stringify_pairs(pairs):

xystr_list=[]

for xy in pairs:

(x, y)=xy

xystr=str(x)+str(y)

xystr_list.append(xystr)

return(xystr_list)

stringify_pairs([(1,"hi"),(True,False),(3,4)])