title: Python regular expressions - find a string in a file that occurs somewhere before another string?
body: <p>My programming knowledge is very limited, I would really appreciate any help on this possibly obvious problem!</p>
  
  <p>Lets say I have a text file, that somewhere contains the text: "I own <strong>two</strong> (Some text in between...) <strong>bicycles</strong>." </p>
  
  <p>How could I for example change two to three? Meaning I need a function to find the string "bicycles" and then look to the left until it somewhere finds the string "two" and changes that.</p>