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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "669999d9",
+   "metadata": {},
+   "source": [
+    "Задача 1. Лог запуска процесса\n",
+    "Напиши функцию log_job_start, которая принимает:\n",
+    "    job_name\n",
+    "    level=\"INFO\"\n",
+    "    env=\"dev\"\n",
+    "Функция должна выводить строку:\n",
+    "    [INFO] Job load_users started in dev"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "2af8c0ea",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "[INFO] Job load_users started in dev\n"
+     ]
+    }
+   ],
+   "source": [
+    "def log_job_start(job_name, level = \"INFO\", env = \"dev\"):\n",
+    "    print(f\"[{level}] {job_name} load_users started in {env}\")\n",
+    "\n",
+    "log_job_start(\"Job\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "60ce459d",
+   "metadata": {},
+   "source": [
+    "Задача 2. Подключение к источнику\n",
+    "Напиши функцию connect_source, которая принимает:\n",
+    "    source_name\n",
+    "    host=\"localhost\"\n",
+    "    port=5432\n",
+    "    user=\"etl_user\"\n",
+    "Функция должна возвращать словарь с настройками подключения."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "d73d7ab5",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "{'source_name': 'dwh', 'host': 'localhost', 'port': 5432, 'user': 'etl_user'} <class 'dict'>\n"
+     ]
+    }
+   ],
+   "source": [
+    "def connect_source(source_name, host = \"localhost\", port = 5432, user = \"etl_user\"):\n",
+    "    connecting_configuration = {\n",
+    "        \"source_name\" : source_name,\n",
+    "        \"host\" : host,\n",
+    "        \"port\" : port,\n",
+    "        \"user\" : user\n",
+    "    }\n",
+    "    return connecting_configuration"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "e667db79",
+   "metadata": {},
+   "source": [
+    "Задача 3. Построение SELECT-запроса\n",
+    "Напиши функцию build_select_query, которая принимает:\n",
+    "    table_name\n",
+    "    columns=None\n",
+    "Логика:\n",
+    "    если columns=None, функция должна вернуть:\n",
+    "        SELECT * FROM table_name\n",
+    "    если список колонок передан, собрать их через запятую."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 51,
+   "id": "4b710ebe",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'SELECT id, user_id, email FROM orders'"
+      ]
+     },
+     "execution_count": 51,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "def build_select_query(table_name, columns = None):\n",
+    "    if columns is None:\n",
+    "        return f\"SELECT * FROM {table_name}\"\n",
+    "    else:\n",
+    "        columns_str = \", \".join(columns)\n",
+    "        return f\"SELECT {columns_str} FROM {table_name}\"\n",
+    "\n",
+    "build_select_query(\"orders\")\n",
+    "build_select_query(\"orders\", [\"id\", \"user_id\", \"email\"])\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "ba059bd5",
+   "metadata": {},
+   "source": [
+    "Задача 4. Проверка обязательных полей\n",
+    "Напиши функцию validate_row, которая принимает:\n",
+    "    row — словарь;\n",
+    "    required_fields=None\n",
+    "Логика:\n",
+    "    если required_fields=None, использовать [\"id\"];\n",
+    "    проверить, есть ли все нужные поля;\n",
+    "    если какого-то поля нет, вернуть строку:\n",
+    "        Missing field: email\n",
+    "    если всё хорошо, вернуть:\n",
+    "        Row is valid"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "ceb7c30b",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'Row is valid'"
+      ]
+     },
+     "execution_count": 55,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "def validate_row(row, required_fields = None):\n",
+    "    if required_fields is None:\n",
+    "        required_fields = [\"id\"]\n",
+    "    for field in required_fields:\n",
+    "        if field not in required_fields:\n",
+    "            return f\"Missing field: {field}\"\n",
+    "        else:\n",
+    "            return \"Row is valid\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.13.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}