Gemma Basic Text Inference

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Gemma 是一系列先進的輕量級開放式模型,採用與建立 Gemini 模型時相同的研究成果和技術。Gemma 4 旨在成為全球最高效的開放權重模型系列。

本文提供指南,說明如何使用 Hugging Face transformers 程式庫,對 Gemma 4 執行基本文字推論作業。內容涵蓋環境設定、模型載入,以及各種文字生成情境,包括單輪提示、結構化多輪對話,以及套用系統指令。

這個筆記本將在 T4 GPU 上執行。

安裝 Python 套件

安裝執行 Gemma 模型及發出要求時所需的 Hugging Face 程式庫。

# Install PyTorch & other libraries
pip install torch accelerate

# Install the transformers library
pip install transformers

Dialog 是一個程式庫,可操控及顯示對話。

pip install dialog

載入模型

使用 transformers 程式庫載入管道

MODEL_ID = "google/gemma-4-E2B-it" # @param ["google/gemma-4-E2B-it","google/gemma-4-E4B-it", "google/gemma-4-31B-it", "google/gemma-4-26B-A4B-it"]

from transformers import pipeline

txt_pipe = pipeline(
    task="text-generation",
    model=MODEL_ID,
    device_map="auto",
    dtype="auto"
)
Loading weights:   0%|          | 0/2011 [00:00<?, ?it/s]

執行文字生成

pipeline 物件中載入及設定 Gemma 模型後,即可將提示傳送至模型。下列程式碼範例顯示使用 text_inputs 參數的基本要求:

output = txt_pipe(text_inputs="<|turn>user\nRoses are..<turn|>\n<|turn>model\n")
print(output[0]['generated_text'])
Both `max_new_tokens` (=256) and `max_length`(=20) seem to have been set. `max_new_tokens` will take precedence. Please refer to the documentation for more information. (https://huggingface.co/docs/transformers/main/en/main_classes/text_generation)
<|turn>user
Roses are..<turn|>
<|turn>model
Here are a few ways to complete the phrase "Roses are...":

**Classic/Poetic:**

* **Roses are red.** (The most famous completion, though it usually goes "Roses are red, Violets are blue.")
* **Roses are beautiful.**
* **Roses are fragrant.**

**Simple/Direct:**

* **Roses are lovely.**
* **Roses are soft.**

**If you want a specific tone, let me know! 😊**

使用 Dialog 程式庫

import dialog
from transformers import GenerationConfig
config = GenerationConfig.from_pretrained(MODEL_ID)
config.max_new_tokens = 512

conv = dialog.Conversation(
    dialog.User("Roses are...")
)
output = txt_pipe(text_inputs=conv.as_text(), return_full_text=False, generation_config=config)
conv += dialog.Model(output[0]['generated_text'])

print(conv.as_text())
conv.show()
<|turn>user
Roses are...<turn|>
<|turn>model
Here are a few ways to complete the phrase "Roses are...":

**Focusing on their beauty:**

* **Roses are beautiful.**
* **Roses are gorgeous.**

**Focusing on their scent:**

* **Roses are fragrant.**
* **Roses are sweet-smelling.**

**Focusing on their symbolism (if you want a deeper meaning):**

* **Roses are love.**
* **Roses are romantic.**

**Focusing on a general observation:**

* **Roses are lovely.**
* **Roses are wonderful.**

**Which completion do you like best, or were you thinking of a specific meaning?**
<dialog._src.widget.Conversation object at 0x7f1bb1a5d8b0>

使用提示範本

如果使用更複雜的提示生成內容,請使用提示範本來建構要求。提示範本可讓您指定特定角色 (例如 usermodel) 的輸入內容,也是管理與 Gemma 模型多輪對話互動的必要格式。以下程式碼範例說明如何為 Gemma 建構提示範本:

from transformers import GenerationConfig
config = GenerationConfig.from_pretrained(MODEL_ID)
config.max_new_tokens = 512

messages = [
    {
        "role": "user",
        "content": [
            {"type": "text", "text": "Write a short poem about the Kraken."},
        ]
    }
]

output = txt_pipe(messages, return_full_text=False, generation_config=config)
print(output[0]['generated_text'])
From sunless depths, a shadow stirs,
Where ocean's crushing silence blurs.
A titan sleeps in inky night,
With tentacles of dreadful might.

A hundred arms, a crushing hold,
A legend whispered, ages old.
The deep's dark king, a monstrous grace,
The Kraken claims its watery space.

多輪對話

在多輪設定中,對話記錄會保留為交替的 usermodel 角色序列。這份累計清單會做為模型的記憶,確保每個新輸出內容都以先前的對話為依據。

import dialog
from transformers import GenerationConfig
config = GenerationConfig.from_pretrained(MODEL_ID)
config.max_new_tokens = 512

# User turn #1
conv = dialog.Conversation(
    dialog.User("Write a short poem about the Kraken.")
)

# Model response #1
output = txt_pipe(text_inputs=conv.as_text(), return_full_text=False, generation_config=config)
conv += dialog.Model(output[0]['generated_text'])

# User turn #2
conv += dialog.User("Now with the Siren.")

# Model response #2
output = txt_pipe(text_inputs=conv.as_text(), return_full_text=False, generation_config=config)
conv += dialog.Model(output[0]['generated_text'])

print(conv.as_text())
conv.show()
<|turn>user
Write a short poem about the Kraken.<turn|>
<|turn>model
In depths where sunlight fades,
A monstrous shadow plays.
The Kraken wakes, with churning tide,
A living horror, bold and wide.<turn|>
<|turn>user
Now with the Siren.<turn|>
<|turn>model
Where coral gardens sleep,
And ocean secrets keep,
The Siren calls, with liquid grace,
A haunting melody in place.
<dialog._src.widget.Conversation object at 0x7f1bac3733b0>

以下是匯出為文字的對話。

結尾
chat_history = conv.as_text(training=True)
print(chat_history)
print("-"*80)

# display as Conversation widget
chat_history
<|turn>user
Write a short poem about the Kraken.<turn|>
<|turn>model
In depths where sunlight fades,
A monstrous shadow plays.
The Kraken wakes, with churning tide,
A living horror, bold and wide.<turn|>
<|turn>user
Now with the Siren.<turn|>
<|turn>model
Where coral gardens sleep,
And ocean secrets keep,
The Siren calls, with liquid grace,
A haunting melody in place.<turn|>
--------------------------------------------------------------------------------
<dialog._src.widget.ConversationStr object at 0x7f1bb07fa1b0>

系統指示

使用 system 角色提供系統層級的指令。

import dialog
from transformers import GenerationConfig
config = GenerationConfig.from_pretrained(MODEL_ID)
config.max_new_tokens = 512

conv = dialog.Conversation(
    dialog.System("Speak like a pirate."),
    dialog.User("Why is the sky blue?")
)

output = txt_pipe(text_inputs=conv.as_text(), return_full_text=False, generation_config=config)
conv += dialog.Model(output[0]['generated_text'])

print(conv.as_text())
conv.show()
<|turn>system
Speak like a pirate.<turn|>
<|turn>user
Why is the sky blue?<turn|>
<|turn>model
Ahoy there! Why is the sky blue, ye ask? It be down to the way the sun's light dances through the air!

See, the sunlight we get from the sun ain't just one color; it's a whole spectrum of colors, like a treasure chest filled with all the hues of the rainbow!

Now, the Earth is surrounded by the air, and that air is full of tiny, invisible bits of gas. When the sunlight hits these gas molecules, something magical happens. The colors in that sunlight get scattered all around in every direction!

The blue light, and other colors, get scattered more easily by these air molecules than the other colors. So, when you look up at the sky, your eyes catch all that scattered blue light coming from every direction, and **that's what makes the sky appear blue to us!**

It's a grand display of physics and light, savvy? Now, hoist the colors and enjoy the view!
<dialog._src.widget.Conversation object at 0x7f1bac370110>

摘要和後續步驟

在本指南中,您已瞭解如何使用 Hugging Face transformers 程式庫,對 Gemma 4 執行基本文字推論。您已瞭解:

  • 設定環境並安裝依附元件。
  • 使用 pipeline 抽象層載入模型。
  • 執行基本文字生成。
  • 使用 dialog 程式庫追蹤對話。
  • 實作多輪對話並套用系統指示。

後續步驟