File output of multiples

# Define the values
x = 3
y = 5

# Create a file
f = open('C:\Users\user_name\My Documents\python.txt', 'w')
n = x
while n < 1000: # Until the multiples reach 1000, this keeps going
    f.write(n) # Writes each result to the text file
    n += x
    f.write("End of 3") # This signifies the end of the multiples of 3 in the file
n = y
while n < 1000: # Same thing as above
    f.write(n)
    n += y
f.close()