How to animate elements?
Let's combine some of the things you've learned to create compelling
animations in your app.
```python
progress_bar = st.progress(0)
status_text = st.empty()
chart = st.line_chart(np.random.randn(10, 2))
for i in range(100):
    # Update progress bar.
    progress_bar.progress(i + 1)
new_rows = np.random.randn(10, 2)
# Update status text.
status_text.text(
    'The latest random number is: %s' % new_rows[-1, 1])
# Append data to the chart.
chart.add_rows(new_rows)
# Pretend we're doing some computation that takes time.
time.sleep(0.1)
status_text.text('Done!')
st.balloons()
```
