<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def delete_project(self):

 """
 Delete the current project without deleting the files in the directory.
 """

        if self.current_active_project:
            self.switch_to_plugin()
            path = self.current_active_project.root_path
            buttons = QMessageBox.Yes | QMessageBox.No
            answer = QMessageBox.warning(
                self,
                _("Delete"),
                _("Do you really want to delete <b>{filename}</b>?<br><br>"
                  "<b>Note:</b> This action will only delete the project. "
                  "Its files are going to be preserved on disk."
                  ).format(filename=osp.basename(path)),
                buttons)
            if answer == QMessageBox.Yes:
                try:
                    self.close_project()
                    shutil.rmtree(osp.join(path, '.spyproject'))
                except EnvironmentError as error:
                    QMessageBox.critical(
                        self,
                        _("Project Explorer"),
                        _("<b>Unable to delete <i>{varpath}</i></b>"
                          "<br><br>The error message was:<br>{error}"
                          ).format(varpath=path, error=to_text_string(error)))