Where is stdout?

[Andrej Mitrovic]

>From TDPL, page 161:

import std.conv;

void writeln(T...)(T args)
{
    foreach (arg; args)
    {
        stdout.rawWrite(to!string(arg));
    }
    stdout.rawWrite('\n');
    stdout.flush();
}

void main()
{
    writeln("test");
}

test.d(10): Error: undefined identifier stdout