title: system call in python
body: <p>i want to make a system call in my python code but the problem is that it breaks the sequence of my original code.. </p>
  
  <p>for ex.</p>
  
  <pre><code>def call_host(self):
      self.builder.get_object("windowMain").show()         
      os.system('python Adder.py')
      self.builder.get_object("window1").show()
  </code></pre>
  
  <p>in above pygtk code once Adder.py is called next line wont execute i want system to execute adder.py and come back to my original code...
  thnx in advance</p>
  
  <p>Here is my code for Adder.py</p>
  
  <pre><code>import sys
  try:  
      import pygtk  
      pygtk.require("2.0")  
  except:  
      pass  
  try:  
      import gtk  
  except:  
      print("GTK Not Availible")
      sys.exit(1)
  
  class adder:
      result = 0
  
      def __init__( self, number1, number2 ):    
          return None            
  
      def giveResult( self,number1,number2 ):    
          self.result = int( number1 ) + int( number2 )    
          return str(self.result)
  
  class adderGui:    
      def __init__( self ):    
          self.builder = gtk.Builder()    
          self.builder.add_from_file("Adder.glade")
  
          dic = { 
              "on_buttonQuit_clicked" : self.quit,    
              "on_buttonAdd_clicked" : self.add,    
              "on_windowMain_destroy" : self.quit,    
          }
  
          self.builder.connect_signals( dic )
  
      def add(self, widget):    
          entry1 = self.builder.get_object ("entry1")    
          entry2 = self.builder.get_object ("entry2")
  
          try:    
              thistime = adder( entry1.get_text(), entry2.get_text() )
          except ValueError:    
              self.builder.get_object("hboxWarning").show()    
              self.builder.get_object("entryResult").set_text("ERROR")    
              return 0
  
          self.builder.get_object("hboxWarning").show()
  
          #self.builder.get_object("image1").hide()
  
          self.builder.get_object("entryResult").set_text(
              thistime.giveResult(entry1.get_text(), entry2.get_text())
          )
  
      def quit(self, widget):    
          sys.exit(0)
  
  adderGui = adderGui()    
  gtk.main()
  </code></pre>