Use parameter name ("sep") in read_csv to comply to newer pandas version

Author: FidoDido1982

pandas_datareader/nasdaq_trader.py

@@ -69,7 +69,7 @@ def _download_nasdaq_symbols(timeout):
     with warnings.catch_warnings(record=True):
         data = read_csv(
             StringIO("\n".join(lines[:-1])),
-            "|",
+            sep="|",
             dtype=_TICKER_DTYPE,
             converters=converter_map,
             index_col=1,