import sys
from numpy.test.testing import *

set_package_path()
# make sure that all yyy symbols are imported before the del statement:
from yyy import fun
del sys.path[0]

class test_fun(ScipyTestCase):
    def check_simple(self, level=1):
        assert fun()=='Hello from yyy.fun'
    #...

if __name__ == "__main__":
    ScipyTest().run()