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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 show(self, app_path, browser=None, new='tab'):
        ''' Opens an app in a browser window or tab.

        This method is useful for testing or running Bokeh server applications
        on a local machine but should not call when running Bokeh server for
        an actual deployment.

        Args:
            app_path (str) : the app path to open
                The part of the URL after the hostname:port, with leading slash.

            browser (str, optional) : browser to show with (default: None)
                For systems that support it, the **browser** argument allows
                specifying which browser to display in, e.g. "safari", "firefox",
                "opera", "windows-default" (see the ``webbrowser`` module
                documentation in the standard lib for more details).

            new (str, optional) : window or tab (default: "tab")
                If ``new`` is 'tab', then opens a new tab.
                If ``new`` is 'window', then opens a new window.

        Returns:
            None

        '''
        if not app_path.startswith("/"):
            raise ValueError("app_path must start with a /")


        address_string = 'localhost'
        if self.address is not None and self.address != '':
            address_string = self.address
        url = "http://%s:%d%s%s" % (address_string, self.port, self.prefix, app_path)

        from bokeh.util.browser import view
        view(url, browser=browser, new=new)