code: def test_valid_init():
      pair = TradingPair(USD, BTC)
      assert pair
      assert pair.base == USD
      assert pair.quote == BTC
  
imports: import pytest
  from tensortrade.oms.instruments import TradingPair, BTC, USD
  from tensortrade.core.exceptions import InvalidTradingPair
label_desc: Use image node_id 1 for calling a global function with example usage: test_valid_init() without return types