Whether the automaton is complete, i.e., there is a transition from each state for each label.
Precondition:
See also:
import vcsn
a = vcsn.context('lal_char(a), z').expression('a*').standard()
a
a.is_complete()
a = vcsn.context('lal_char(ab), z').expression('a*').standard()
a
a.is_complete()