python write to txt file with open code example

Example 1: python writing to text file

f = open("demofile2.txt", "a")
f.write("Now the file has more content!")
f.close()

#open and read the file after the appending:
f = open("demofile2.txt", "r")
print(f.read())

Example 2: read and write file in python

#Write a Python program to create a file of numbers by taking input from the user and then display the content of the file. You can take input of non-zero numbers, with an appropriate prompt, from the user until the user enters a zero to create the file assuming that the numbers are non-zero.  
    f = open ('NumFile.txt','w')
    while True :
        no = int(input("enter a number (0 for exit)"))
        if no == 0 :
            print("you entered zero(0) ....... \n now you are exit  !!!!!!!!!!!")
            break
        else :
            f.write(str(no)+"\n")
    f.close() 
    f1 = open ('NumFile.txt','r')
    print("\ncontent of file :: \n",f1.read())
    f1.close()