<s>[INST] <<SYS>>
You are a helpful, respectful and honest assistant. Always answer as helpfully as possible, while being safe.  Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature.
If a question does not make any sense, or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
<</SYS>>

Extract from the following context the minimal span word for word that best answers the question. Think step by step and explain your reasoning. Then give the answer in JSON format as follows:
```json
{
  "answer": ...
}
```
If the answer is not in the context, the answer should be "?".
Question: من قاد الحكومة النهائية لجمهورية روسيا الاتحادية الاشتراكية السوفياتية ؟
Context: كانت الحكومة تعرف رسميا باسم مجلس مفوضي الشعب ( 1917 - 1946 ) ومجلس الوزراء ( 1946 - 1978 ) ومجلس الوزراء - الحكومة ( 1978 - 1991 ) . ترأس الحكومة الأولى فلاديمير لينين بصفته " رئيس مجلس مفوضي الشعب في الاتحاد السوفياتي الروسي " والأخير بوريس يلتسين كرئيس للحكومة ورئيس الدولة تحت عنوان " الرئيس " . [/INST] ```json
{<answer_start>
  "answer": "بوريس يلتسين"
  <answer_end>
}
``` </s>
كانت الحكومة تعرف رسميا باسم مجلس مفوضي الشعب ( 1917 - 1946 ) ومجلس الوزراء ( 1946 - 1978 ) ومجلس الوزراء - الحكومة ( 1978 - 1991 ) . ترأس الحكومة الأولى فلاديمير لينين بصفته " رئيس مجلس مفوضي الشعب في الاتحاد السوفياتي الروسي " والأخير بوريس يلتسين كرئيس للحكومة ورئيس الدولة تحت عنوان " الرئيس " .
من قاد الحكومة النهائية لجمهورية روسيا الاتحادية الاشتراكية السوفياتية ؟
{'answer_start': [222], 'text': ['بوريس يلتسين']}