title: Deploying python-gst. have some problem about query_position(Gst.Format.TIME)
body: <p>I'm trying to deploy a program running the binding of gstreamer in python (python-gst)</p>
  <pre><code>pipeline_str = &quot;filesrc name=src ! decodebin name=dec ! queue ! videoscale ! videorate ! videoconvert ! textoverlay name=textoverlay ! ximagesink name=sink force-aspect-ratio=True qos=True handle-expose=False&quot;
  
  pipeline = Gst.parse_launch(pipeline_str)
  filesrc = pipeline.get_by_name(&quot;src&quot;)
  filesrc.set_property(&quot;location&quot;, filepath)
  </code></pre>
  <p>and when i print:</p>
  <pre><code>print(&quot;pipeline_query_position&quot;,pipeline.query_position(Gst.Format.TIME))
  </code></pre>
  <p>it's return :
  (False, cur=-1)</p>
  <p>i wanna know how to fix this error or where am  i wrong.
  Thanks everyone for helping</p>