title: How to while loop until the end of a file in Python without checking for empty line?
body: <p>I'm writing an assignment to count the number of vowels in a file, currently in my class we have only been using code like this to check for the end of a file:</p>
  
  <pre><code>vowel=0
  f=open("filename.txt","r",encoding="utf-8" )
  line=f.readline().strip()
  while line!="":
      for j in range (len(line)):
          if line[j].isvowel():
              vowel+=1
  
      line=f.readline().strip()
  </code></pre>
  
  <p>But this time for our assignment the input file given by our professor is an entire essay, so there are several blank lines throughout the text to separate paragraphs and whatnot, meaning my current code would only count until the first blank line.</p>
  
  <p>Is there any way to check if my file has reached its end other than checking for if the line is blank? Preferably in a similar fashion that I have my code in currently, where it checks for something every single iteration of the while loop</p>
  
  <p>Thanks in advance</p>