How to extract data from URL/ HTML?

Im trying to extract the IP address that is nested in html and print it out to a string.

<ul>

<li>IP Address:

<span class="darktext">199.123.456.789</span>

</li>

<li>Internet Service Provider:

<span class="darktext">Optimum WiFi</span>

</li>

<li>City:

<span class="darktext">My City</span>

</li>

<li>State/Region:

<span class="darktext">New City</span>

</li>

<li>Country:

<span class="darktext">United States</span>

</li>

<li>Browser:

<span class="darktext">TextFromURL</span>

</li>

<li>Operating System:

<span class="darktext"></span>

</li>

<li>Screen Resolution:

<span id="resolution" class="darktext"></span>

</li>

</ul>