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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_welcome_client(self):

 """Create a welcome client with some instructions."""

        if self.tabwidget.count() == 0:
            welcome = open(WELCOME).read()
            client = NotebookClient(self, WELCOME, ini_message=welcome)
            self.add_tab(client)
            return client