# Example
To take a minimal example, the following asserts the default behaviour of the DigitalInOut
-constructor, to configure a pin as an input with no pull. The gc.collect() calls help to
-minimise heap fragmentation, and ensure there is enough memory to run the particular test.
+constructor, checks the behaviour of switch_to_input/output(), configures a pin as a pull-up button, a pull-down button and an LED.
```python
import testing