how can i use 'plotly.graph_objs' to visualize volume datas?

You can use the `plotly.graph_objs` module to create a variety of visualizations, including those that display volume data. Here's an example of how to use this module to create a 3D visualization of volume data:

import plotly.graph_objs as go
import numpy as np

# Generate some fake volume data
x, y, z = np.mgrid[-10:10:20j, -10:10:20j, -10:10:20j]
values = x * x * 0.5 + y * y + z * z * 2

# Create the 3D volume trace
trace = go.Volume(
    x=x.flatten(),
    y=y.flatten(),
    z=z.flatten(),
    value=values.flatten(),
    isomin=10,
    isomax=50,
    opacity=0.1, # set opacity for the volume
    surface_count=17, # number of isosurface values
    colorscale='Viridis', # set colorscale
)

# Create the layout
layout = go.Layout(
    title='3D Volume Visualization',
    margin=dict(l=0, r=0, b=0, t=40),
    scene=dict(
        xaxis=dict(title='X'),
        yaxis=dict(title='Y'),
        zaxis=dict(title='Z')
    )
)

# Create the figure
fig = go.Figure(data=[trace], layout=layout)

# Show the figure
fig.show()

In this example, we start by generating some fake volume data using the `numpy` module. We then create a `go.Volume` trace object, which takes in the x, y, and z coordinates of the data, as well as the values at each point. We also set a few other parameters, such as the opacity and colorscale.

Next, we create a layout object, which sets the title and axis labels for the visualization. Finally, we create a `go.Figure` object, which combines the trace and layout objects, and show the figure using the `show()` method.

Note that the `plotly` library provides many other types of traces and customization options, so you can experiment with different settings to create the visualization that best suits your needs.