code: def test_vecangle_2(x1, y1, x2, y2):
      v0 = pt(0, 0)
      v1 = pt(x1, y1)
      v2 = pt(x2, y2)
  
      try:
          alpha = vecangle(v1, v2)
      except ValueError:  # math domain error in some edge cases?
          return
  
      if np.allclose(v1, v0) or np.allclose(v2, v0):
          assert np.isnan(alpha)
      else:
          assert 0 <= alpha <= np.pi
  
imports: import math
  import pytest
  from hypothesis import given
  import hypothesis.strategies
  import numpy
  from pdftabextract.geom import pt, ptdist, vecangle, vecrotate, overlap, lineintersect, rect, rectcenter, rectarea, rectintersect, normalize_angle, normalize_angle_halfcircle, project_polarcoord_lines
label_desc: Use image node_id 4 for calling a global function with example usage: test_vecangle_2(x1, y1, x2, y2) without return types