fixes

src/tools/data_loader.py

@@ -1,9 +1,7 @@
-import sys
 import sqlite3
-from typing import Dict, Tuple
+from typing import Dict
 import pandas as pd
 
-from tools.trading_pair import TradingPair
 
 
 def load_sqlite_to_dataframe(db_path, query):
@@ -15,15 +13,15 @@ def load_sqlite_to_dataframe(db_path, query):
     except sqlite3.Error as excpt:
         print(f"SQLite error: {excpt}")
         raise
-    except Exception as e:
+    except Exception as excpt:
         print(f"Error: {excpt}")
-        raise
+        raise Exception() from excpt
     finally:
         if "conn" in locals():
             conn.close()
 
 
-def convert_time_to_UTC(value: str, timezone: str):
+def convert_time_to_UTC(value: str, timezone: str) -> str:
 
     from zoneinfo import ZoneInfo
     from datetime import datetime
@@ -32,12 +30,9 @@ def convert_time_to_UTC(value: str, timezone: str):
     local_dt = datetime.strptime(value, "%Y-%m-%d %H:%M:%S")
 
     zinfo = ZoneInfo(timezone)
-    result = local_dt.replace(tzinfo=zinfo)
+    result: datetime = local_dt.replace(tzinfo=zinfo).astimezone(ZoneInfo("UTC"))
 
-    result = result.astimezone(ZoneInfo("UTC"))
-    result = result.strftime("%Y-%m-%d %H:%M:%S")
-
-    return result
+    return result.strftime("%Y-%m-%d %H:%M:%S")
 
 
 def load_market_data(datafile: str, config: Dict) -> pd.DataFrame:
@@ -52,7 +47,7 @@ def load_market_data(datafile: str, config: Dict) -> pd.DataFrame:
 
     query = "select"
     if security_type == "CRYPTO":
-        query += " strftime('%Y-%m-%d %H:%M:%S', tstamp/1000000000, 'unixepoch') as tstamp"
+        query += " strftime('%Y-%m-%d %H:%M:%S', tstamp_ns/1000000000, 'unixepoch') as tstamp"
         query += ", tstamp as time_ns"
     else:
         query += " tstamp"