add some improvements

Author: Joaopeuko

mqpy/book.py

@@ -53,4 +53,5 @@ def release(self) -> bool:
         Returns:
             bool: True if successful, False otherwise.
         """
-        return Mt5.market_book_release(self.symbol)
+        result = Mt5.market_book_release(self.symbol)
+        return False if result is None else result

tests/test_book.py

@@ -91,45 +91,35 @@ def test_full_workflow(symbol):
 
 def test_multiple_symbols():
     """Test using Book with multiple symbols simultaneously."""
-    # Get available symbols
     symbols = Mt5.symbols_get()
     if len(symbols) < 2:
         pytest.skip("Need at least 2 symbols for this test")
 
-    # Select two different symbols
     symbol1 = symbols[0].name
     symbol2 = symbols[1].name
 
-    # Create books for both symbols
     book1 = Book(symbol1)
     book2 = Book(symbol2)
 
-    # Wait for market books to populate
     time.sleep(1)
 
-    # Get market data for both symbols
     data1 = book1.get()
     data2 = book2.get()
 
-    # Verify both returned data
     assert data1 is not None
     assert data2 is not None
 
-    # Clean up
     book1.release()
     book2.release()
 
 def test_unavailable_symbol(caplog):
     """Test behavior with an unavailable symbol."""
     caplog.set_level(logging.ERROR)
 
-    # Use an invalid symbol name
     invalid_symbol = "INVALID_SYMBOL_THAT_DOESNT_EXIST"
 
-    # Create a book with invalid symbol
     book = Book(invalid_symbol)
 
-    # Check that an error was logged
     assert "Error adding INVALID_SYMBOL_THAT_DOESNT_EXIST to the market book" in caplog.text
 
     release_result = book.release()