def tweets(stock_symbol, start=None, end=None):
"""Return tweets for a stock symbol between two epoch timestamps."""
company_name = settings.STOCK_SYMBOL_MAPPINGS[stock_symbol]
try:
company_file = open(file_handler.filename_for_company(company_name))
except:
return {}
data = json.loads(company_file.read())
if start or end:
data = _filter_on_date(data, company_name, start, end)
return data
