code: def test_valid_marker_cycles():
      fig, ax = plt.subplots()
      ax.set_prop_cycle(cycler(marker=[1, "+", ".", 4]))
  
file_path: matplotlib/lib/matplotlib/tests/test_cycles.py
imports: import contextlib
  from io import StringIO
  import matplotlib
  import matplotlib.pyplot
  import numpy
  import pytest
  from cycler import cycler
label_desc: Use image node_id 3 for calling a global function with example usage: test_valid_marker_cycles() without return types