import string
#open the input file
infile = open("loops.py", "r")

#open the output file
outfile = open("loops2.py", "w")

#read each line
for line in infile:
    #print line
    #use an if statement to determine if an i is present on the line
    if 'i ' in line:
        #line2 = string.replace(line, "i ", "x ")
        #replace i with x
        line = line.replace("i ", "x ")
    else:
        line = line
    #store line in outputfile
    outfile.write(line)

infile.close()
outfile.close()