code: def test_streamplot():
      x = np.arange(-60, 42.5, 2.5)
      y = np.arange(30, 72.5, 2.5)
      x2d, y2d = np.meshgrid(x, y)
      u = np.cos(np.deg2rad(y2d))
      v = np.cos(2.0 * np.deg2rad(x2d))
      mag = (u**2 + v**2) ** 0.5
      plot_extent = [-60, 40, 30, 70]
      fig = plt.figure(figsize=(6, 3))
      ax = fig.add_subplot(projection=ccrs.NorthPolarStereo())
      ax.set_extent(plot_extent, crs=ccrs.PlateCarree())
      ax.coastlines()
      ax.streamplot(
          x,
          y,
          u,
          v,
          transform=ccrs.PlateCarree(),
          density=(1.5, 2),
          color=mag,
          linewidth=2 * mag,
      )
      return fig
  
imports: import re
  import matplotlib.colors
  import matplotlib.pyplot
  import numpy
  import pytest
  import cartopy.crs
  from cartopy.mpl import _MPL_38
  from cartopy.tests.conftest import requires_scipy
label_desc: Use image node_id 39 for calling a global function with example usage: test_streamplot() and returns: fig