如何解决AttributeError：'_ Environ'对象没有属性'has_key'

def _is_dev_mode():
    # quick hack to check if the program is running in dev mode.
    # if 'has_key' in os.environ  
    if os.environ.has_key('SERVER_SOFTWARE') \
        or os.environ.has_key('PHP_FCGI_CHILDREN') \
        or 'fcgi' in sys.argv or 'fastcgi' in sys.argv \
        or 'mod_wsgi' in sys.argv:
           return False
    return True
def _is_dev_mode():
    # quick hack to check i