进制转换的Python代码问题

这是我的代码，是为了实现把输入的的k进制转为十进制。
可以帮我看看，要怎么改吗
lst=[]
a=input('请输入要转为十进制的数：')
k=eval(input('该数的进制数是：'))
lst.append(a)
n=len(a)
i=1
b=0
while i>n:

for c in range(lst):
    b=b+lst(c) * k**(i-1)
    i+=1
    b=bi

print(bi)
print(lst)

int内置函数就能解决你的问题，python解释器下，help(int)
class int(object)
| int([x]) -> integer
| int(x, base=10) -> integer
|
| Convert a number or string to an integer, or return 0 if no arguments
| are given. If x is a number, return x.int(). For floating point
| numbers, this truncates towards zero.
|
| If x is not a number or if base is given, then x must be a string,
| bytes, or bytearray instance representing an integer literal in the
| given base. The literal can be preceded by '+' or '-' and be surrounded
| by whitespace. The base defaults to 10. Valid bases are 0 and 2-36.
| Base 0 means to interpret the base from the string as an integer literal.
| >>> int('0b100', base=0)
| 4
|