How to hide legend with Plotly Express and Plotly in Python?

# importing packages
import plotly.express as px

# using the gapminder dataset
df = px.data.tips()
fig = px.scatter(df, x="total_bill", y="tip", color="sex", 
                 symbol="smoker", facet_col="time",
                 labels={"sex": "Gender", "smoker": "Smokes"})

# hiding legend in pyplot express.
fig.update_traces(showlegend=False)

fig.show()

import plotly.graph_objects as go

# using the Figure dataset
fig = go.Figure()

fig.add_trace(go.Line(name="first", x=["a", "b"], y=[1,3]))
fig.add_trace(go.Line(name="second", x=["a", "b"], y=[2,1]))
fig.add_trace(go.Line(name="third", x=["a", "b"], y=[1,2]))
fig.add_trace(go.Line(name="fourth", x=["a", "b"], y=[2,3]))


# hiding legend in pyplot express.
fig.update(layout_showlegend=False)

fig.show()

import plotly.express as px

# using the iris dataset
df = px.data.iris()

# plotting the line chart
fig = px.line(df, y="sepal_width", line_dash='species',
            color='species')

# hiding legend in pyplot express.
fig.update_traces(showlegend=False)

# showing the plot
fig.show()