C :

#include<stdio.h>
#include<string.h>

void main(){
    char a[1000];
    int i;
    scanf("%s",&a[i]);
	
    for(i=0;i<strlen(a);i++){
    	if(a[i]=='O'){
    		a[i]='0';
		}
		if(a[i]=='l'){
    		a[i]='1';
		}
		if(a[i]=='Z'){
    		a[i]='2';
		}
		if(a[i]=='S'){
    		a[i]='5';
		}
		if(a[i]=='b'){
    		a[i]='6';
		}
		if(a[i]=='B'){
    		a[i]='8';
		}
		if(a[i]=='q'){
    		a[i]='9';
		}
    }
    printf("%s",a);
}

Python :

m=input()
s=list(m)
n=len(m)
for i in range(0,n):
    if s[i]=="O" :
        s[i]="0"
    elif s[i]=="l" :
        s[i]="1"
    elif s[i]=="Z" :
        s[i]="2"
    elif s[i]=="S" :
        s[i]="5"
    elif s[i]=="b" :
        s[i]="6"
    elif s[i]=="B" :
        s[i]="8"
    elif s[i]=="q" :
        s[i]="9"
print("".join(s))