python for循环的迭代
#什么是迭代：更新换代l=[12,1,25,3]for i in l: print(i)iter_l=l.__iter__()print(iter_l.__next__())#相当于for的迭代index=0while index < len(l): print(l[index]) index+=1m=open('a.txt','r+')iter_m...
