'Update the list of completions'

def update_completions(self):

    self.original_cursor_pos = cpos = self.cursorPosition()
    text = unicode(self.text())
    prefix = text[:cpos]
    complete_prefix = prefix.lstrip()
    if self.sep:
        complete_prefix = prefix.split(self.sep)[(-1)].lstrip()
    self.mcompleter.set_completion_prefix(complete_prefix)
