int initialSize = map.size();
      V oldValue = map.put(keyToPut, valueToPut);
      assertEquals(valueToPut, map.get(keyToPut));
      assertTrue(map.containsKey(keyToPut));
      assertTrue(map.containsValue(valueToPut));
      assertEquals(initialSize + 1, map.size());
      assertNull(oldValue);
    } else {
      assertThrows(UnsupportedOperationException.class, () -> map.put(keyToPut, valueToPut));
    }

        ci += 4;
        SMBUtil.writeInt2(0x10, ctx, ci); // NameOffset
        SMBUtil.writeInt2(4, ctx, ci + 2); // NameLength
        ci += 4;
        // Reserved (2) + DataOffset (2)
        // Put data at offset 0x20
        SMBUtil.writeInt2(0, ctx, ci); // Reserved
        SMBUtil.writeInt2(0x20, ctx, ci + 2); // DataOffset
        ci += 4;
        SMBUtil.writeInt4(8, ctx, ci); // DataLength
        ci += 4;

Temporarily adopting this point of view (of the *external developer*) can help you feel like it's more obvious where to put the parameters, the Pydantic model for the body, for the response, etc. for that *external API*.

///

### Create a callback `APIRouter` { #create-a-callback-apirouter }

```
.
├── app
│   ├── __init__.py
│   ├── main.py
└── static/
```

### Download the files { #download-the-files }

Download the static files needed for the docs and put them on that `static/` directory.

You can probably right-click each link and select an option similar to "Save link as...".

**Swagger UI** uses the files:

            <T> T getUserData(String key) {
                getUserData()[key]
            }

            @Override
            <T> void putUserData(String key, T value) {
                getUserData().put(key, value)
            }
        }
        rule
    }

To declare a **request** body, you use [Pydantic](https://docs.pydantic.dev/) models with all their power and benefits.

/// info

To send data, you should use one of: `POST` (the more common), `PUT`, `DELETE` or `PATCH`.

Sending a body with a `GET` request has an undefined behavior in the specifications, nevertheless, it is supported by FastAPI, only for very complex/extreme use cases.

  @Override
  public @Nullable V put(K key, V value) {
    checkNotNull(key);
    checkNotNull(value);
    int hash = hash(key);
    return segmentFor(hash).put(key, hash, value, false);
  }

  @Override
  public @Nullable V putIfAbsent(K key, V value) {
    checkNotNull(key);
    checkNotNull(value);
    int hash = hash(key);
    return segmentFor(hash).put(key, hash, value, true);
  }

Those worker processes would be the ones running your application, they would perform the main computations to receive a **request** and return a **response**, and they would load anything you put in variables in RAM.

<img src="/img/deployment/concepts/process-ram.drawio.svg">

And of course, the same machine would probably have **other processes** running as well, apart from your application.

Since HTTP requests frequently happen in parallel, connection pooling must be thread-safe.

	data, err := json.Marshal(userInfo)
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	writeSuccessResponseJSON(w, data)
}

// UpdateGroupMembers - PUT /minio/admin/v3/update-group-members
func (a adminAPIHandlers) UpdateGroupMembers(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	objectAPI, _ := validateAdminReq(ctx, w, r, policy.AddUserToGroupAdminAction)