input: Write a Python function to design a trading strategy that maximizes profits while minimizing risks.
  assert trading_strategy({"AAPL": 10, "MSFT": 5}) == {"AAPL": 15, "MSFT": 5}
  assert trading_strategy({"GOOGL": 8, "AMZN": 3}) == {"GOOGL": 10, "AMZN": 3}
  assert trading_strategy({"TSLA": 12, "NFLX": 6}) == {"TSLA": 16, "NFLX": 6}
output: def trading_strategy(portfolio):
      for stock, shares in portfolio.items():
          if shares >= 10:
              portfolio[stock] += 5
      return portfolio