Show values of lollipop-chart

Hello guys

Im new to visualizing data and im trying to make a lollipop-chart just as this one: data visualization - What is the name of this plot that has rows with two connected dots? - Cross Validated

But im failing with the Annotate:

# Annotate
for row in df.itertuples():
    ax.text(row.Index, y2_new+.5, s=round(y2_new, 2), horizontalalignment= 'center', verticalalignment='bottom', fontsize=14)

This is my code:

x3 = ["Alter: 0-29","Alter: 30-59","Alter: 60+"]
y3_new =[20, 44, 34]
y2_new =[13, 43, 43]

plt.hlines(y=x3, xmin = y3_new , xmax = y2_new, color='skyblue', alpha=0.4)
plt.scatter(y2_new, x3, color='#0096d7', s=50, label='Jazzmusiker', zorder=10)
plt.scatter(y3_new, x3, color='green', s=50 , label='Bluesmusiker', zorder=10)
plt.legend()


# Add title and axis names
plt.title("Sterbealter der Jazz- und Bluesmusiker", loc='left')
plt.xlabel('Value of the variables')
plt.ylabel('Alter')


# Annotate
for row in df.itertuples():
    ax.text(row.Index, y2_new+.5, s=round(y2_new, 2), horizontalalignment= 'center', verticalalignment='bottom', fontsize=14)

# Show the graph
plt.show()

What error do you get. The code above does not define df.