import matplotlib
import matplotlib.pyplot as plt
import mpld3
from mpld3 import plugins


def create_plot():
    fig, ax = plt.subplots()
    ax.plot([1, 3], [1, 2])
    fmtr = matplotlib.ticker.StrMethodFormatter("{x:.2f}")
    ax.xaxis.set_major_formatter(fmtr)
    ax.set_title('Tickformat str method test', size=14)
    return fig


def test_date():
    fig = create_plot()
    _ = mpld3.fig_to_html(fig)
    plt.close(fig)


if __name__ == "__main__":
    mpld3.show(create_plot())

import matplotlib
import matplotlib.pyplot as plt
import mpld3
from mpld3 import plugins


def create_plot():
    fig, ax = plt.subplots()
    ax.plot([1, 3], [1, 2])
    fmtr = matplotlib.ticker.StrMethodFormatter("{x:.2f} :)")
    ax.xaxis.set_major_formatter(fmtr)
    ax.set_title('Tickformat str method test', size=14)
    return fig


def test_date():
    fig = create_plot()
    _ = mpld3.fig_to_html(fig)
    plt.close(fig)


if __name__ == "__main__":
    mpld3.show(create_plot())

Clarify purpose of test by...adding a smiley!