code: def test_np_matmul():
      # GH26650
      df1 = pd.DataFrame(data=[[-1, 1, 10]])
      df2 = pd.DataFrame(data=[-1, 1, 10])
      expected = pd.DataFrame(data=[102])
  
      result = np.matmul(df1, df2)
      tm.assert_frame_equal(expected, result)
  
imports: from collections import deque
  import re
  import string
  import numpy
  import pytest
  import pandas.util._test_decorators
  import pandas
  import pandas._testing
  from pandas.arrays import SparseArray
label_desc: Use image node_id 17 for calling a global function with example usage: test_np_matmul() without return types