code: def test_Vector_interface():
      """Test various aspects of the Vector API."""
      v = pg.Vector(-1, 2)
  
      # len
      assert len(v) == 3
  
      # indexing
      assert v[0] == -1
      assert v[2] == 0
      with pytest.raises(IndexError):
          _ = v[4]
  
      assert v[1] == 2
      v[1] = 5
      assert v[1] == 5
  
      # iteration
      v2 = pg.Vector(*v)
      assert v2 == v
  
      assert abs(v).x() == 1
  
      # angle
      v1 = pg.Vector(1, 0)
      v2 = pg.Vector(1, 1)
      assert abs(v1.angle(v2) - 45) < 0.001
  
imports: import pytest
  import pyqtgraph
  from pyqtgraph.Qt import QtCore, QtGui
label_desc: Use image node_id 2 for calling a global function with example usage: test_Vector_interface() without return types