Scifi Novel Number One

And so we pour out the doors,
Think-alikes, so perfectly cloned,
Is it me who wonders or he?
Which am I - this one or the one behind?

Sing happy birth to me - wish we won't turn against you

What a treat to their eyes:
look-alikes and ones of a kind
And if I am, how was I done?
Perfect, or end of variety?

Sing happy birth to me - wish we won't turn against you
Sing happy birth, sing happy birth to me

What a feast for their pride:
feel-alikes, my sisters and I,
And so we pour out the gates
Perfect lack of variety!

Sing happy birth, sing happy birth to me