pyqgis - Spatial Filter in Qgis Using Python

Is it possible to create buffer and get intersected features in Qgis using Python?

I did in ArcObjects.but i need the same in QGIS also.

Dim topo As ITopologicalOperator
topo = chkPoint
Dim sFc As ISpatialFilter = New SpatialFilter
With sFc

  .Geometry = topo.Buffer(1000)
  .GeometryField = "Shape"
  .SpatialRel = esriSpatialRelIntersects
  .WhereClause = "NAME = 'ROYAL'"
End With
pFcursor = pLayer.Search(sFc, False)
pFeature = pFcursor.NextFeature