assertThrows(
        NullPointerException.class, () -> multimap().putAll(k3(), Lists.newArrayList(v3(), null)));

    Collection<V> values = multimap().get(k3());
    if (values.size() == 0) {
      expectUnchanged();
      // Be extra thorough in case internal state was corrupted by the expected null.
      assertEquals(Lists.newArrayList(), Lists.newArrayList(values));
      assertEquals(size, multimap().size());
    } else {

import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A list which forwards all its method calls to another list. Subclasses should override one or
 * more methods to modify the behavior of the backing list as desired per the <a

    final List<Object> overriddenAndAnnotatedInSubclassEvents = Lists.newArrayList();
    final List<Object> differentlyOverriddenNotAnnotatedInSubclassBadEvents = Lists.newArrayList();
    final List<Object> differentlyOverriddenAnnotatedInSubclassBadEvents = Lists.newArrayList();

    @Subscribe
    public void notOverriddenInSubclass(Object o) {
      notOverriddenInSubclassEvents.add(o);
    }

    @Subscribe

    }
    return dummy;
  }

  @Benchmark
  int copyArrayList(int reps) {
    int size = this.size;
    int dummy = 0;
    for (int rep = 0; rep < reps; rep++) {
      List<Object> builder = Lists.newArrayList();
      for (int i = 0; i < size; i++) {
        builder.add(OBJECT);
      }
      dummy += ImmutableList.copyOf(builder).size();
    }
    return dummy;
  }

  @Benchmark

    }
    return dummy;
  }

  @Benchmark
  int copyArrayList(int reps) {
    int size = this.size;
    int dummy = 0;
    for (int rep = 0; rep < reps; rep++) {
      List<Object> builder = Lists.newArrayList();
      for (int i = 0; i < size; i++) {
        builder.add(OBJECT);
      }
      dummy += ImmutableList.copyOf(builder).size();
    }
    return dummy;
  }

  @Benchmark

      assertTrue(multimap().asMap().remove(key) instanceof List);
    }
  }

  @CollectionSize.Require(SEVERAL)
  public void testEquals() {
    resetContainer(mapEntry(k0(), v0()), mapEntry(k1(), v0()), mapEntry(k0(), v3()));
    Map<K, Collection<V>> expected = Maps.newHashMap();
    expected.put(k0(), Lists.newArrayList(v0(), v3()));
    expected.put(k1(), Lists.newArrayList(v0()));

import com.google.common.collect.Lists;
import com.google.common.eventbus.Subscribe;
import com.google.common.eventbus.outside.NeitherAbstractNorAnnotatedInSuperclassTest.SubClass;
import java.util.List;

public class NeitherAbstractNorAnnotatedInSuperclassTest extends AbstractEventBusTest<SubClass> {
  static class SuperClass {
    final List<Object> neitherOverriddenNorAnnotatedEvents = Lists.newArrayList();

    final List<Object> annotatedIn1Events = Lists.newArrayList();
    final List<Object> annotatedIn1And2Events = Lists.newArrayList();
    final List<Object> annotatedIn1And2AndClassEvents = Lists.newArrayList();
    final List<Object> declaredIn1AnnotatedIn2Events = Lists.newArrayList();
    final List<Object> declaredIn1AnnotatedInClassEvents = Lists.newArrayList();

    List<Integer> list = emptyList();
    Iterator<Integer> iterator = peekingIterator(new ThrowsAtEndIterator<Integer>(list));
    assertNextThrows(iterator);

    /* Checks the case where a later element throws an exception. */

    list = Lists.newArrayList(1, 2);
    iterator = peekingIterator(new ThrowsAtEndIterator<Integer>(list));
    assertTrue(iterator.hasNext());

```

////

This will make `tags` be a list, although it doesn't declare the type of the elements of the list.

## List fields with type parameter

But Python has a specific way to declare lists with internal types, or "type parameters":

### Import typing's `List`

In Python 3.9 and above you can use the standard `list` to declare these type annotations as we'll see below. 💡