<execute_python>
# 1) Parse intent & constraints (quantity and item name)
import re
from tinydb import Query
from datetime import datetime

# Lowercase version for parsing
req = user_request

# Attempt to extract quantity and product name from the return request
return_match = re.search(r"return\s+(\d+)\s+([A-Za-z]+)", req, re.IGNORECASE)
if not return_match:
    # Missing quantity or item name
    STATUS = "invalid_request"
    answer_text = "I can help with that—how many pairs would you like to return?"
    print(f"LOG: ACTION=read DRY_RUN=False STATUS={STATUS}")
else:
    qty = int(return_match.group(1))
    item_name = return_match.group(2)

    # 2) Query inventory for matching item
    Item = Query()
    matches = inventory_tbl.search(Item.name.test(lambda v, target=item_name: v.lower() == target.lower()))

    if not matches:
        # No such item in inventory
        STATUS = "no_match"
        answer_text = f"We don’t have any '{item_name}' sunglasses to return. Could you check the name?"
        print(f"LOG: ACTION=read DRY_RUN=False STATUS={STATUS}")
    else:
        # Found the item; perform the return (restock and refund)
        item = matches[0]
        unit_price = item['price']
        refund_amount = unit_price * qty

        # 3) Update inventory stock
        new_stock = item['quantity_in_stock'] + qty
        inventory_tbl.update({'quantity_in_stock': new_stock}, Item.item_id == item['item_id'])

        # 4) Record transaction for the refund
        prev_balance = get_current_balance(transactions_tbl)
        new_balance = prev_balance - refund_amount
        txn_id = next_transaction_id(transactions_tbl)
        transaction = {
            'transaction_id': txn_id,
            'customer_name': 'RETURN',
            'transaction_summary': f"Return of {qty} {item['name']}",
            'transaction_amount': -refund_amount,
            'balance_after_transaction': new_balance,
            'timestamp': datetime.now().isoformat()
        }
        transactions_tbl.insert(transaction)

        # 5) Prepare success response
        STATUS = "success"
        answer_text = f"Your return of {qty} {item['name']} sunglasses has been processed and a refund of ${refund_amount} issued."
        print(f"LOG: ACTION=mutate DRY_RUN=False STATUS={STATUS}")
</execute_python>