Alternative hypotheses (a.k.a. n-best list).
.. attribute:: transcript
Transcript text representing the words that
the user spoke.
Output only. The confidence estimate between 0.0 and 1.0. A
higher number indicates an estimated greater likelihood that
the recognized words are correct. This field is set only for
the top alternative. This field is not guaranteed to be
accurate and users should not rely on it to be always
provided. The default of 0.0 is a sentinel value indicating
confidence was not set.