def slow(t):
t.slow = True<EOL>return t<EOL>
Label a test as 'slow'.

The exact definition of a slow test is obviously both subjective and
hardware-dependent, but in general any individual test that requires more
than a second or two should be labeled as slow (the whole suite consits of
thousands of tests, so even a second is significant).

Parameters
----------
t : callable
    The test to label as slow.

Returns
-------
t : callable
    The decorated test `t`.

Examples
--------
The `numpy.testing` module includes ``import decorators as dec``.
A test can be decorated as slow like this::

  from numpy.testing import *

  @dec.slow
  def test_big(self):
      print 'Big, slow test'