TimeField rendering in admin forms

[Tomek Rej]

When passing a datetime.Time instance to the choices parameter in a TimeField, the admin template converts it to a human readable form. Eg Time(0, 0) gets converted to "midnight", Time(1, 30) gets converted to 1:30 a.m. In Django 1.10 it gets formatted as 00:00:00 and 01:30:00 respectively.

An example of the choices I pass in to the constructor is:

[
    (datetime.Time(0, 0), '00:00'),
    (datetime.Time(0, 30), '00:30'),
    (datetime.Time(1, 0), '01:00'),
    ....,
    (datetime.Time(23, 30), '23:30')
]

This causes the admin form validation to fail with errors like the following:
Select a valid choice. midnight is not one of the available choices.