Add simplified pstn examples (#1822)

* Add simplified pstn examples
* Add daily_twilio_sip_dial_out example

examples/phone-chatbot/daily-pstn-dial-in/utils/daily_helpers.py

@@ -0,0 +1,76 @@
+"""Helper functions for interacting with the Daily API."""
+
+import os
+from typing import Dict, Optional
+
+import aiohttp
+from dotenv import load_dotenv
+
+from pipecat.transports.services.helpers.daily_rest import (
+    DailyRESTHelper,
+    DailyRoomParams,
+    DailyRoomProperties,
+    DailyRoomSipParams,
+)
+
+load_dotenv()
+
+
+# Initialize Daily API helper
+async def get_daily_helper(session: Optional[aiohttp.ClientSession] = None) -> DailyRESTHelper:
+    """Get a Daily REST helper with the configured API key."""
+    if session is None:
+        session = aiohttp.ClientSession()
+
+    return DailyRESTHelper(
+        daily_api_key=os.getenv("DAILY_API_KEY", ""),
+        daily_api_url=os.getenv("DAILY_API_URL", "https://api.daily.co/v1"),
+        aiohttp_session=session,
+    )
+
+
+async def create_daily_room(
+    session: Optional[aiohttp.ClientSession] = None, caller_phone: str = "unknown-caller"
+) -> Dict[str, str]:
+    """Create a Daily room with SIP capabilities for phone calls.
+
+    Args:
+        session: Optional aiohttp session to use for API calls
+        caller_phone: The phone number of the caller to use in display name
+
+    Returns:
+        Dictionary with room URL, token, and SIP endpoint
+    """
+    daily_helper = await get_daily_helper(session)
+
+    # Configure SIP parameters
+    sip_params = DailyRoomSipParams(
+        display_name=caller_phone,
+        video=False,
+        sip_mode="dial-in",
+        num_endpoints=1,
+    )
+
+    # Create room properties with SIP enabled
+    properties = DailyRoomProperties(
+        sip=sip_params,
+        enable_dialout=True,  # Needed for outbound calls if you expand the bot
+        enable_chat=False,  # No need for chat in a voice bot
+        start_video_off=True,  # Voice only
+    )
+
+    # Create room parameters
+    params = DailyRoomParams(properties=properties)
+
+    # Create the room
+    try:
+        room = await daily_helper.create_room(params=params)
+        print(f"Created room: {room.url} with SIP endpoint: {room.config.sip_endpoint}")
+
+        # Get token for the bot to join
+        token = await daily_helper.get_token(room.url, 24 * 60 * 60)  # 24 hours validity
+
+        return {"room_url": room.url, "token": token, "sip_endpoint": room.config.sip_endpoint}
+    except Exception as e:
+        print(f"Error creating room: {e}")
+        raise