human
Complete the below
@pytest.fixture()
def failing_fetch_strategy():

    ''''Returns a fetch strategy that fails.'
    '''
 What is a the Python program you requested?
assistant
#Here is the Python program you requested.
    class FailingFetchStrategy(spack.fetch_strategy.FetchStrategy, ):
        def fetch(self):
            raise spack.fetch_strategy.FailedDownloadError('<non-existent    URL>', 'This    implementation    of    FetchStrategy    always    fails')
    return FailingFetchStrategy()