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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 valid_project(self):

 """Handle an invalid active project."""

        try:
            path = self.projects.get_active_project_path()
        except AttributeError:
            return

        if bool(path):
            if not self.projects.is_valid_project(path):
                if path:
                    QMessageBox.critical(
                        self,
                        _('Error'),
                        _("<b>{}</b> is no longer a valid Spyder project! "
                          "Since it is the current active project, it will "
                          "be closed automatically.").format(path))
                self.projects.close_project()