<p>I need help with python</p><p>I need function for standard deviation<img alt="" src="http://d2vlcm61l7u1fs.cloudfront.net/media%2F9a2%2F9a265556-baa6-4754-9ec8-aaf6fb8dcc67%2Fphp01IkN3.png" style="height:156px;width:666px;"/></p><p>it is not hard to make function from numpy, but I am not allowedto import numpy library</p><p>how do