import numpy as np

def linfit(x, y):
    """
    Return linear fit
    """
    p = np.polyfit(x, y, 1)
    f = np.poly1d(p)
    x_fit = np.linspace(min(x), max(x), 100)
    y_fit = f(x_fit)
    yhat = f(x)
    ybar = np.sum(y)/len(y)
    ssreg = np.sum((yhat - ybar)**2)
    sstot = np.sum((y - ybar)**2)
    R2 = ssreg / sstot
    return (p, x_fit, y_fit, R2)

def test():
    return np.ones(5)


def test2(name, x=None, y=None):
    print (name,x,y)
    ret = y*x  
    print (ret)
    return ret

def add(x,y,z):
    return x+y+z

def read_dev(dev):
    return dev.read()