title: Python : Remove everything after a specific character (,)
body: <p>I have millions of lines inside a file (9GB)(can't opened by Notepad++) and i want to remove all the words after a specific characters. (,)</p>
  
  <p>Example of line : </p>
  
  <p>data1,data2,data3,data4</p>
  
  <p>I want to keep the (data1) and delete everything else.</p>
  
  <p>Thanks in advance.</p>