ONNX Float32 to Float16

#Convert to ONNX ModelProto object and save model binary file:
from onnxmltools.utils.float16_converter import convert_float_to_float16_model_path
new_onnx_model = convert_float_to_float16_model_path('model.onnx')
onnx.save(new_onnx_model, 'new_model.onnx')

Example 1: Convert ONNX ModelProto object:
from onnxmltools.utils.float16_converter import convert_float_to_float16
new_onnx_model = convert_float_to_float16(onnx_model)

Example 2: Convert ONNX model binary file:
from onnxmltools.utils.float16_converter import convert_float_to_float16
from onnxmltools.utils import load_model, save_model
onnx_model = load_model('model.onnx')
new_onnx_model = convert_float_to_float16(onnx_model)
save_model(new_onnx_model, 'new_model.onnx')