Python内置函数bin() oct()等实现进制转换

使用Python内置函数：bin()、oct()、int()、hex()可实现进制转换。
先看Python官方文档中对这几个内置函数的描述：
bin(x)
Convert an integer number to a binary string. The result is a valid Python expression. If x is not a Python int object,it has to define an __index__() method that returns an integer.
oct(x)
Convert an integer number to an octal string. The result is a valid Python expression. If x is not a Python int object,it has to define an __index__() method that returns an integer.
int([number | string[,base]])
Convert a number or string to an integer. If no arguments are given,return 0. If a number is given,return number.__int__(). Conversion of floating point numbers to integers truncates towards zero. A string must be a base-radix integer literal optionally preceded by ‘+' or ‘-‘ (with no space in between) and optionally surrounded by whitespace. A base-n literal consists of the digits 0 to n-1,with ‘a' to ‘z' (or ‘A' to ‘Z') having values 10 to 35. The default base is 10. The allowed values are 0 and 2-36. Base-2,-8,and -16 literals can be optionally prefixed with 0b/0B,0o/0O,or 0x/0X,as with integer literals in code. Base 0 means to interpret exactly as a code literal,so that the actual base is 2,8,10,or 16,and so that int('010',0) is not legal,while int('010') is,as well as int('010',8).
hex(x)
Convert an integer number to a hexadecimal string. The result is a valid Python expression. If x is not a Python int object,it has to define an __index__() method that returns an integer.

↓	2进制	8进制	10进制	16进制
2进制	-	bin(int(x,8))	bin(int(x,10))	bin(int(x,16))
8进制	oct(int(x,2))	-	oct(int(x,10))	oct(int(x,16))
10进制	int(x,2)	int(x,8)	-	int(x,16)
16进制	hex(int(x,2))	hex(int(x,8))	hex(int(x,10))	-

bin()、oct()、hex()的返回值均为字符串，且分别带有0b、0o、0x前缀。