feat: added a util function for converting datetimes to iso 8601 strings

pyzipline/utils.py

@@ -11,3 +11,14 @@ def convert_str_to_datetime(date_string: str) -> datetime:
         datetime: Datetime object
     """
     return datetime.strptime(date_string, '%Y-%m-%dT%H:%M:%S.%fZ')
+
+def convert_datetime_to_str(datetime: datetime) -> str:
+    """Converts a datetime object to a Zipline (`ISO 8601`) date string
+
+    Args:
+        datetime: Datetime to convert
+
+    Returns:
+        str: Converted date string
+    """
+    return datetime.now().strftime('%Y-%m-%dT%H:%M:%S.%fZ')