executor.execute(() -> {
            try {
                final Object eventType = dataMap.remove(getParamValue(localParams, "field.event_type", "event_type"));
                if (getParamValue(localParams, "event.create", "create").equals(eventType)
                        || getParamValue(localParams, "event.modify", "modify").equals(eventType)) {
                    // updated file
                    addDocument(localParams, dataMap);

## First Steps

Let's see a very simple example. It will be so simple that it is not very useful, for now.

But this way we can focus on how the **Dependency Injection** system works.

### Create a dependency, or "dependable"

Let's first focus on the dependency.

It is just a function that can take all the same parameters that a *path operation function* can take:

public class MultisetContainsTester<E> extends AbstractMultisetTester<E> {
  @CollectionSize.Require(absent = ZERO)
  public void testContainsAllMultisetIgnoresFrequency() {
    assertTrue(getMultiset().containsAll(getSubjectGenerator().create(e0(), e0(), e0())));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testContainsAllListIgnoresFrequency() {
    assertTrue(getMultiset().containsAll(asList(e0(), e0(), e0())));
  }

    super(false, true, true, true);
  }

  @Override
  TreeBasedTable<String, Integer, Character> makeTable() {
    TreeBasedTable<String, Integer, Character> table = TreeBasedTable.create();
    table.put("a", 1, 'a');
    table.put("z", 1, 'a');
    return table;
  }

  @Override
  protected Map<String, Map<Integer, Character>> makePopulatedMap() {

public class MultisetContainsTester<E> extends AbstractMultisetTester<E> {
  @CollectionSize.Require(absent = ZERO)
  public void testContainsAllMultisetIgnoresFrequency() {
    assertTrue(getMultiset().containsAll(getSubjectGenerator().create(e0(), e0(), e0())));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testContainsAllListIgnoresFrequency() {
    assertTrue(getMultiset().containsAll(asList(e0(), e0(), e0())));
  }

            return updateEntity(source, result);
        } catch (InstantiationException | IllegalAccessException e) {
            final String msg = "Cannot create a new instance: " + entityType.getName();
            throw new IllegalBehaviorStateException(msg, e);
        }
    }

```

////

//// tab | Python 3.8+

```Python hl_lines="34"
{!> ../../docs_src/body_updates/tutorial002.py!}
```

////

### Using Pydantic's `update` parameter

Now, you can create a copy of the existing model using `.model_copy()`, and pass the `update` parameter with a `dict` containing the data to update.

/// info

            return updateEntity(source, result);
        } catch (InstantiationException | IllegalAccessException e) {
            final String msg = "Cannot create a new instance: " + entityType.getName();
            throw new IllegalBehaviorStateException(msg, e);
        }
    }

    protected <RESULT extends ClickLog> RESULT updateEntity(Map<String, Object> source, RESULT result) {

            result.setName(DfTypeUtil.toString(source.get("name")));
            return updateEntity(source, result);
        } catch (InstantiationException | IllegalAccessException e) {
            final String msg = "Cannot create a new instance: " + entityType.getName();
            throw new IllegalBehaviorStateException(msg, e);
        }
    }

    protected <RESULT extends Group> RESULT updateEntity(Map<String, Object> source, RESULT result) {

            return updateEntity(source, result);
        } catch (InstantiationException | IllegalAccessException e) {
            final String msg = "Cannot create a new instance: " + entityType.getName();
            throw new IllegalBehaviorStateException(msg, e);
        }
    }