\section{Exercises}
\begin{footnotesize} 
\begin{enumerate}\setcounter{enumi}{-1}
	\item  1. There are no exercises for this chapter. Congratulations on completing the book! 

    \vspace{1em}
    Here is some bonus code for you!
\begin{lstlisting}
import numpy as np
import plotly.graph_objects as go

theta = np.linspace(0, 2*np.pi, 200)
f_x = np.cos(theta)
f_y = np.sin(theta)

left = (-0.3, 0.4)
right = (0.3, 0.4)

m_theta = np.linspace(0, np.pi, 100)
m_x = 0.5 * np.cos(m_theta)
m_y = -0.4 + 0.2 * -np.sin(m_theta)
m_x = 0.66*np.cos(theta)
m_y = -abs(0.66*np.sin(theta))

fig = go.Figure()

fig.add_scatter(x=f_x, y=f_y, #fill='toself', mode='lines',
                line_color='black', #fillcolor='yellow'
                )

fig.add_scatter(x=[left[0]], y=[left[1]], mode='markers',
                marker=dict(size=20, color='black'))

fig.add_scatter(x=[right[0]], y=[right[1]], mode='markers',
                marker=dict(size=20, color='black'))

fig.add_scatter(x=m_x, y=m_y, mode='lines', line=dict(width=4, color='black'))

fig.update_layout(
    title="Congratulations!",
    template = "simple_white",
    paper_bgcolor='yellow',  
    plot_bgcolor='yellow',
    xaxis=dict(showgrid=False, zeroline=False, visible=False),
    yaxis=dict(showgrid=False, zeroline=False, visible=False),
    width=500,
    height=500,
    margin = dict(l = 40, r = 40, t = 40, b = 40),
    showlegend=False
)

fig.update_yaxes(scaleanchor="x", scaleratio=1)
fig.show("png")
\end{lstlisting}
\end{enumerate}
\end{footnotesize} 
