"Pulsing Purple Pythons"

  Well, perhaps not quite right,  ordinary brown snakes.

 They think they are welcome to hang out in my shed.

 They haven't got the story right, they are not welcome there at all.

Now I open it with caution, asking is there anyone inside.
 
I remove my hat and sunglasses to get a good look inside.

Yep, there they are a wiggling, and jiggling all about.

I close the door, behind me and leave a parting word.

If you really think you are welcome.

Please wait for your invitation, I will pop it in the mail.

Please don't hold your breath while waiting.

I might be lucky enough and you will all expire.