human
Complete this python program:
def login_as_coach(context, coach_name='mrpibb', coach_pass='abc123'):
assistant
#Here is the Python code you requested.

    """Log in as a coach specified by the optional arguments, or create
    such a user and log in if it doesn\t exist.
    :context: a behave context, used for its browser
    :coach_name: optional. username of the coach.
    :coach_pass: optional. password of the coach.
    """
    if (not FacilityUser.objects.filter(username=coach_name)):
        class ContextWithMixin(FacilityMixins, ):
            def __init__(self):
                self.browser = context.browser
        context_wm = ContextWithMixin()
        context_wm.create_teacher(username=coach_name, password=coach_pass)
    facility = FacilityUser.objects.get(username=coach_name).facility.id
    _login_user(context, coach_name, coach_pass, facility=facility)