title: Delete rows if there are null values in a specific column in Pandas dataframe
body: <p><a href="https://i.stack.imgur.com/51zQ4.png" rel="noreferrer"><img src="https://i.stack.imgur.com/51zQ4.png" alt="enter image description here" /></a></p>
  <p>I'm new to python pandas. Need some help with deleting a few rows where there are null values. In the screenshot, I need to delete rows where <code>charge_per_line == &quot;-&quot;</code> using python pandas.</p>