get_hist_data
Get historical stock market data
Args:
symbol: Stock symbol/ticker
interval: Time interval ('minute','hour','day','week','month','year')
interval_multiplier: Interval multiplier (default: 1)
start_date: Start date in YYYY-MM-DD format (default: '1970-01-01')
end_date: End date in YYYY-MM-DD format (default: '2030-12-31')
adjust: Adjustment type ('none', 'qfq', 'hfq') (default: 'none')
source: Data source ('eastmoney', 'sina') (default: 'eastmoney')
