reading, writing lines from txt file From https://www.guru99.com/reading-and-writing-files-in-python.html
def main():
f= open("guru99.txt","w+")
#f=open("guru99.txt","a+")
for i in range(10):
f.write("This is line %d\r\n" % (i+1))
f.close()
#Open the file back and read the contents
#f=open("guru99.txt", "r")
# if f.mode == 'r':
# contents =f.read()
# print contents
#or, readlines reads the individual line into a list
#fl =f.readlines()
#for x in fl:
#print x
if __name__== "__main__":
main()