(self, file)
return os.popen(cmd, 'r')
t.open_r(file) and t.open_w(file) implement
        t.open(file, 'r') and t.open(file, 'w') respectively.
t.open_r(file) and t.open_w(file) implement
        t.open(file, 'r') and t.open(file, 'w') respectively.
t . open_r ( file ) and t . open_w ( file ) implement t . open ( file r ) and t . open ( file w ) respectively .
def open_r(self, file):
        """t.open_r(file) and t.open_w(file) implement
        t.open(file, 'r') and t.open(file, 'w') respectively."""
        if not self.steps:
            return open(file, 'r')
        if self.steps[-1][1] == SINK:
            raise ValueError('Template.open_r: pipeline ends width SINK')
        cmd = self.makepipeline(file, '')
        return os.popen(cmd, 'r')
def open_r ( self , file ) : if not self . steps : return open ( file , 'r' ) if self . steps [ - 1 ] [ 1 ] == SINK : raise ValueError ( 'Template.open_r: pipeline ends width SINK' ) cmd = self . makepipeline ( file , '' ) return os . popen ( cmd , 'r' )