gpt-5-nano

import openai

client = openai.OpenAI(
    api_key="your-api-key",
    base_url="https://api.vsellm.ru/v1"
)

response = client.chat.completions.create(
    model="openai/gpt-5-nano",
    messages=[
        {"role": "user", "content": "Привет!"}
    ]
)

print(response.choices[0].message.content)