<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def run_example(example_name, environ):
 """ Run an example module from zipline.examples. """

    mod = EXAMPLE_MODULES[example_name]

    register_calendar("YAHOO", get_calendar("NYSE"), force=True)

    return run_algorithm(
        initialize=getattr(mod, 'initialize', None),
        handle_data=getattr(mod, 'handle_data', None),
        before_trading_start=getattr(mod, 'before_trading_start', None),
        analyze=getattr(mod, 'analyze', None),
        bundle='test',
        environ=environ,
        # Provide a default capital base, but allow the test to override.
        **merge({'capital_base': 1e7}, mod._test_args())
    )