Skip the numpy doctests.

They seem like more trouble that they're worth.

_pytest/python_api.py

@@ -315,7 +315,8 @@ def approx(expected, rel=None, abs=None, nan_ok=False):
 
     And ``numpy`` arrays::
 
-        >>> np.array([0.1, 0.2]) + np.array([0.2, 0.4]) == approx(np.array([0.3, 0.6]))
+        >>> import numpy as np                                                          # doctest: +SKIP
+        >>> np.array([0.1, 0.2]) + np.array([0.2, 0.4]) == approx(np.array([0.3, 0.6])) # doctest: +SKIP
         True
 
     By default, ``approx`` considers numbers within a relative tolerance of

testing/python/approx.py

@@ -350,11 +350,10 @@ class TestApprox(object):
         assert a21 != approx(a12)
 
     def test_doctests(self):
-        np = pytest.importorskip('numpy')
         parser = doctest.DocTestParser()
         test = parser.get_doctest(
                 approx.__doc__,
-                {'approx': approx ,'np': np},
+                {'approx': approx},
                 approx.__name__,
                 None, None,
         )