Prob. 2: Write a program to search a text file and print only those lines which have 
the search word in it. Follow the steps:
(1) Read a word from the input
(2) Store it in a variable named 'searchWord'
(3) Open a text file containing some text
(4) Read line by line from this file
(5) Search for the input word in each line and print the line if it contains the word
(6) Close the file