class_docstr: A pair of financial instruments to be traded on a specific exchange.
  
  Parameters
  ----------
  exchange : `Exchange`
      An exchange that contains the `pair` for trading.
  pair : `TradingPair`
      A trading pair available on the `exchange`.
code: def __repr__(self):
      return str(self)
  
file_path: tensortrade/tensortrade/oms/instruments/exchange_pair.py
imports: from decimal import Decimal
label_desc: Use image node_id 7 for calling the ExchangePair obj's underlying member method code with example usage: obj.__repr__() and returns: str