Fetching specific value from the html response

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1

HTML:

		<div id="iaappcontext" class="test">
			<div id="iacontent">
				<!--suppress HtmlUnknownAttribute -->
				<iframe name='iamain' id='iamain' onload="if (this.src!='' && this.src!=null) {loadIFrames();}"
					scriptLoadsrc="dash.phtml?.op=1877&.nomenu=1&.sess=bHL9IwEZCGaFIHvfwQENqQi-Zocgew..">
				</iframe>

			</div>
		</div>

From the above HTML response, I just want to fetch session information i.e bHL9IwEZCGaFIHvfwQENqQi-Zocgew…

How to do that ?