関連ワード:  python check whether a variable is defined    python check if a variable is defined or not    python check if a variable is set    python check if a variable is declared    python check if a variable is undefined    python check if variable is defined and not empty    python check if variable is defined in class    python check whether a variable exists    python check if environment variable is defined    python check if global variable is defined  
結果 : python check whether a variable is defined