__init__(self, checkpoint_file=None, allowed_keys=None, omitted_keys=None): 

open_checkpoint_file(self, chk): 

Opens the passed checkpoint_file (if not already open)

• chk: str | file-like

• :returns: _

close_checkpoint_file(self, stream): 

Opens the passed checkpoint_file (if not already open)

• chk: Any

• :returns: _

save_parameter(self, key, value): 

Saves a parameter to the checkpoint file

• key: Any

• value: Any

• :returns: _

load_parameter(self, key): 

Loads a parameter from the checkpoint file

• key: Any

• :returns: _

keys(self):