title: How to remove duplicates from QcomboBox in pyqt4 python
body: <p>How to remove duplicates from combobox in pyqt4 . i have tried following code but its not removing duplicates from comboBox.</p>
  
  <p>Code:</p>
  
  <pre><code>from PyQt4 import QtCore, QtGui
  import sys
  app = QtGui.QApplication(sys.argv)
  w = QtGui.QWidget()
  w.resize(500, 388)
  
  combo=QtGui.QComboBox(w)
  combo.setGeometry(QtCore.QRect(150, 50, 251, 31))
  combo.addItem("aa")
  combo.addItem("bb")
  combo.addItem("cc")
  combo.addItem("aa")
  combo.setDuplicatesEnabled(False)
  
  w.setWindowTitle("PyQt")
  w.show()
  sys.exit(app.exec_())
  </code></pre>