input: def generate_html_table(genre: str) -> str:
      """ Generates an HTML table displaying information about the top 10 bestselling books in a specific genre.
      >>> generate_html_table('Fantasy')
      '<table><tr><th>Title</th><th>Author</th><th>Genre</th><th>Sales</th></tr><tr><td>BookTitle1</td><td>Author1</td><td>Fantasy</td><td>1000</td></tr><tr><td>BookTitle2</td><td>Author2</td><td>Fantasy</td><td>900</td></tr><tr><td>BookTitle3</td><td>Author3</td><td>Fantasy</td><td>800</td></tr><tr><td>BookTitle4</td><td>Author4</td><td>Fantasy</td><td>700</td></tr><tr><td>BookTitle5</td><td>Author5</td><td>Fantasy</td><td>600</td></tr><tr><td>BookTitle6</td><td>Author6</td><td>Fantasy</td><td>500</td></tr><tr><td>BookTitle7</td><td>Author7</td><td>Fantasy</td><td>400</td></tr><tr><td>BookTitle8</td><td>Author8</td><td>Fantasy</td><td>300</td></tr><tr><td>BookTitle9</td><td>Author9</td><td>Fantasy</td><td>200</td></tr><tr><td>BookTitle10</td><td>Author10</td><td>Fantasy</td><td>100</td></tr></table>'
      """
output:     table = "<table><tr><th>Title</th><th>Author</th><th>Genre</th><th>Sales</th></tr>"
      for i in range(1, 11):
          table += f"<tr><td>BookTitle{i}</td><td>Author{i}</td><td>{genre}</td><td>{1100 - i * 100}</td></tr>"
      table += "</table>"
      return table