python面试终极准备

简述Python的深浅拷贝？

将列表内的元素,根据位数合并成字典
	lst = [1,2,4,8,16,32,64,128,256,512,1024,32769,65536,4294967296]  

	# 输出
	{
	    1:[1,2,3,8],
	    2:[16,32,64],
	    3:[128,256,512],
	    4:[1024,],
	    5:[32769,65536],
	    6:[4294967296]
	}

list = [1,2,4,8,16,32,64,128,256,512,1024,32769,65536,4294967296]
dict={}
for i in list:
    dict.setdefault(len(str(i)),[]).append(i)
print(dict)

###源码解析
    def setdefault(self, *args, **kwargs): # real signature unknown
        """
        Insert key with a value of default if key is not in the dictionary.

        Return the value for key if key is in the dictionary, else default.
        """
        pass
###
　　

一行999

print('\n'.join([' '.join(['%s*%s=%-2s' % (y, x, x*y) for y in range(1, x+1)]) for x in range(1, 10)]))
#自叹不如
自己最开始研究的

f'{f'{i}*{j}={i*j}' for j in range(1,i+1)}' for i in range(1,10)