Create a binary file with name and roll number. Search for a given roll number and display the name, if not found display appropriate message

import os

def createFile(filename, rollno, name):
    try:
        file = open(filename, "wb")
        file.write(str(rollno) + "," + name + "\n")
        file.close()
        print("File created successfully")
    except IOError as e:
        print("Error in file creation: " + str(e))

def searchFile(filename, rollno):
    try:
        file = open(filename, "rb")
        for line in file:
            roll, name = line.decode().split(",")
            if roll == str(rollno):
                print("Name: " + name)
                break
        else:
            print("Not Found")
        file.close()
    except IOError as e:
        print("Error in file read: " + str(e))

def main():
    filename = input("Enter filename: ")
    ch = 0
    while ch != 3:
        print("1. Create File")
        print("2. Search File")
        print("3