@classmethod
def _from_dict(cls, _dict):
    """Initialize a MemoryUsage object from a json dictionary."""
    args = {}
    if 'used_bytes' in _dict:
        args['used_bytes'] = _dict.get('used_bytes')
    if 'total_bytes' in _dict:
        args['total_bytes'] = _dict.get('total_bytes')
    if 'used' in _dict:
        args['used'] = _dict.get('used')
    if 'total' in _dict:
        args['total'] = _dict.get('total')
    if 'percent_used' in _dict:
        args['percent_used'] = _dict.get('percent_used')
    return cls(**args)
