added CCXTError to py
added CCXTError to py

ccxt/ccxt,thijstriemstra/ccxt,tritoanst/ccxt,thijstriemstra/ccxt,tritoanst/ccxt,ccxt/ccxt,aiueogawa/ccxt,ccxt/ccxt,aiueogawa/ccxt,aiueogawa/ccxt,ccxt/ccxt,ccxt/ccxt,tritoanst/ccxt,aiueogawa/ccxt,tritoanst/ccxt,thijstriemstra/ccxt,thijstriemstra/ccxt