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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 execute_code(self, lines, current_client=True, clear_variables=False):

 """Execute code instructions."""

        sw = self.get_current_shellwidget()
        if sw is not None:
            if sw._reading:
                pass
            else:
                if not current_client:
                    # Clear console and reset namespace for
                    # dedicated clients
                    # See issue 5748
                    try:
                        sw.sig_prompt_ready.disconnect()
                    except TypeError:
                        pass
                    sw.reset_namespace(warning=False)
                elif current_client and clear_variables:
                    sw.reset_namespace(warning=False)
                # Needed to handle an error when kernel_client is none
                # See issue 6308
                try:
                    sw.execute(to_text_string(lines))
                except AttributeError:
                    pass
            self.activateWindow()
            self.get_current_client().get_control().setFocus()