Refactor and translate comments and docstrings in utility modules to English for better clarity and maintainability. Update Gunicorn and application startup messages for consistency in language. Enhance documentation with English translations for better accessibility.

backend_api_python/app/services/live_trading/execution.py

@@ -41,37 +41,37 @@ MT5Client = None
 
 def _normalize_symbol_for_order(symbol: str, market_type: str = "swap") -> str:
     """
-    规范化符号格式，确保符号符合交易所要求。
+    Standardize symbol formats to ensure symbols comply with exchange requirements.
     
-    处理各种输入格式：
+    Handles various input formats:
     - BTC/USDT -> BTC/USDT
     - BTCUSDT -> BTC/USDT
     - BTC/USDT:USDT -> BTC/USDT
-    - PI, TRX -> PI/USDT, TRX/USDT (默认添加 /USDT)
+    - PI, TRX -> PI/USDT, TRX/USDT (/USDT is added by default)
     
     Args:
-        symbol: 原始符号
-        market_type: 市场类型 (spot/swap)
+        symbol: original symbol
+        market_type: market type (spot/swap)
         
     Returns:
-        规范化后的符号
+        normalized symbols
     """
     if not symbol:
         return symbol
     
     sym = symbol.strip()
     
-    # 移除 swap/futures 后缀
+    # Remove swap/futures suffix
     if ':' in sym:
         sym = sym.split(':', 1)[0]
     
     sym = sym.upper()
     
-    # 如果已经有分隔符，直接返回（假设格式正确）
+    # If there is already a separator, return it directly (assuming the format is correct)
     if '/' in sym:
         return sym
     
-    # 尝试从常见报价货币中识别
+    # Try to identify from common quote currencies
     common_quotes = ['USDT', 'USD', 'BTC', 'ETH', 'BUSD', 'USDC']
     for quote in common_quotes:
         if sym.endswith(quote) and len(sym) > len(quote):
@@ -79,7 +79,7 @@ def _normalize_symbol_for_order(symbol: str, market_type: str = "swap") -> str:
             if base:
                 return f"{base}/{quote}"
     
-    # 如果无法识别，默认使用 USDT
+    # If not recognized, USDT will be used by default.
     return f"{sym}/USDT"
 
 
@@ -148,7 +148,7 @@ def place_order_from_signal(
     if mt == "spot" and ("short" in (signal_type or "").lower()):
         raise LiveTradingError("spot market does not support short signals")
     
-    # 规范化符号格式（统一处理裸符号如 PI, TRX 等）
+    # Standardized symbol format (unified processing of bare symbols such as PI, TRX, etc.)
     symbol = _normalize_symbol_for_order(symbol, market_type=mt)
 
     if isinstance(client, BinanceFuturesClient):