def  pcacov(x)
mean = torch.mean(x,1)
xm = x - mean:expandAs(x)
c = torch.mm 13(xm:t(),xm)
c=c:div(x:size(1)-1)
ce,cv = torch.symeig(c,‘V’)
return ce,cv
But got syntax error
xm = xs -    mean:expandAs(xs)
^
SyntaxError: invalid syntax