how to count the total number of lines in a text file using python

Question

For example if my text file is:

blue
green
yellow
black

Here there are four lines and now I want to get the result as four. How can I do th

Answer 1

here is how you can do it through list comprehension, but this will waste a little bit of your computer's memory as line.strip() has been called twice.

     with open('textfile.txt') as file:
lines =[
            line.strip()
            for line in file
             if line.strip() != '']
print("number of lines =  {}".format(len(lines)))