from pathlib import Path

import matplotlib

matplotlib.use("Agg")
import matplotlib.pyplot as plt

output = Path("venv-matplotlib-smoke.png")

fig, ax = plt.subplots(layout="constrained")
ax.plot([1, 2, 3], [1, 4, 9], marker="o")
ax.set_title("Virtual environment smoke test")
ax.set_xlabel("Run")
ax.set_ylabel("Value")
fig.savefig(output)
plt.close(fig)

print(f"matplotlib {matplotlib.__version__}")
print(f"backend {matplotlib.get_backend()}")
print(f"saved: {output}")
print(f"bytes: {output.stat().st_size}")