Plotly express bar chart colour change

How can I change the colour of the plotly express bar-chart to green in the following code?

import plotly.express as px
import pandas as pd

# prepare the dataframe
df = pd.DataFrame(dict(
        x=[1, 2, 3],
        y=[1, 3, 2]
    ))


# prepare the layout
title = "A Bar Chart from Plotly Express"

fig = px.bar(df, 
             x='x', y='y', # data from df columns
             color= pd.Series('green', index=range(len(df))), # does not work
             title=title,
             labels={'x': 'Some X', 'y':'Some Y'})
fig.show()

It can be done:

• with argument color_discrete_sequence = ['green']*3, or,
• with fig.update_traces(marker_color = 'green') after the bar is instantiated.

Ref: Community response