Dash doesn't show figure created with px.imshow

Question

As in the title, Dash doesn't display a figure (picture) created with px.imshow. Below is my code.

import plotly.graph_objects as go # or plotly.express as px
import plotly.express as px
import numpy as np
import dash
import dash_core_components as dcc
import dash_html_components as html

img_rgb = np.array([[[255, 0, 0], [0, 255, 0], [0, 0, 255]],
                    [[0, 255, 0], [0, 0, 255], [255, 0, 0]]
                   ], dtype=np.uint8)
fig = px.imshow(img_rgb)

app = dash.Dash()

app.layout = html.Div([
    dcc.Graph(figure=fig)
])
app.run_server(debug=True)  

I used this documentation page. At the very bottom, it says:

Everywhere in this page that you see fig.show(), you can display the same figure in a Dash application by passing it to the figure argument of the Graph component from the built-in dash_core_components package like this:

import plotly.graph_objects as go # or plotly.express as px
fig = go.Figure() # or any Plotly Express function e.g. px.bar(...)
# fig.add_trace( ... )
# fig.update_layout( ... )

import dash
import dash_core_components as dcc
import dash_html_components as html

app = dash.Dash()
app.layout = html.Div([
    dcc.Graph(figure=fig)
])

app.run_server(debug=True, use_reloader=False)  # Turn off reloader if inside Jupyter

So what am I doing wrong?

Answer 1

The only thing that I changed to make it run is:

from dash import dcc
from dash import html

instead of

import dash_core_components as dcc
import dash_html_components as html