I found the solution at self. It's possible to use the command wait to get a check for the current container state.
import lxc
container = lxc.Container("Test")
container.start()
if container.wait("RUNNING", timeout=5)
container.stop()
container.destroy()
This Command returns a true if it reach the state within the timeout. In other cases returns a false. And so we can make a check for the current container state with the standard library!