def _cast_types(args):
	"""
	This method performs casting to all types of inputs passed via cmd.
	:param args: argparse.ArgumentParser object.
	:return: argparse.ArgumentParser object.
	"""
	args.x_val = None if args.x_val == 'None' else int(args.x_val)
	args.test_size = float(args.test_size)
	args.max_depth = int(args.max_depth)
	args.learning_rate = float(args.learning_rate)
	args.n_estimators = int(args.n_estimators)
	args.verbosity = int(args.verbosity)
	# objective.
	# booster.
	# tree_method.
	args.n_jobs = int(args.n_jobs)
	args.gamma = float(args.gamma)
	args.min_child_weight = int(args.min_child_weight)
	args.max_delta_step = int(args.max_delta_step)
	args.subsample = int(args.subsample)
	args.colsample_bytree = float(args.colsample_bytree)
	args.colsample_bylevel = float(args.colsample_bylevel)
	args.colsample_bynode = float(args.colsample_bynode)
	args.reg_alpha = float(args.reg_alpha)
	args.reg_lambda = float(args.reg_lambda)
	args.scale_pos_weight = float(args.scale_pos_weight)
	args.base_score = float(args.base_score)
	args.random_state = int(args.random_state)
	args.missing = None if args.missing == 'None' else float(args.missing)

	return args