map函数只支持一个参数的函数，需要改造run_and_log函数只接受一个参数，比如：

def run_and_log((function,name)): 
    start=datetime.now()
    print '%s instance %s starts at %s' % (function,name,start)
    function()
    end=datetime.now()
    print '%s instance %s ends at %s,cost %s' % (function,name,start,end-start)