def __init__(self):
    self._begun = False
    self._current_epoch = None
    self._current_step = None
    self._max_steps = None
    self._estimator = None
    self._estimator_locked = False
def __init__(self):
    self._begun = False
    self._current_epoch = None
    self._current_step = None
    self._max_steps = None
    self._estimator = None
    self._estimator_locked = False