modify prime assets field

Author: tigersk

tigeropen/trade/domain/prime_account.py

@@ -9,19 +9,19 @@ class PortfolioAccount:
     """
     prime/paper account assets
     """
-    def __init__(self, account, timestamp=None):
+    def __init__(self, account, update_timestamp=None):
         """
         :param account:
-        :param timestamp: asset update timestamp in milliseconds.
+        :param update_timestamp: asset update timestamp in milliseconds.
         """
         self.account = account
-        self.timestamp = timestamp
+        self.update_timestamp = update_timestamp
         self._segments = dict()
 
     @property
     def segments(self):
         """account information by contract type
-        :return: dict with two keys, 'SEC' for stocks， 'FUT' for futures；
+        :return: dict with two keys, 'S' for stocks， 'C' for commodity futures；
         """
         return self._segments
 
@@ -33,7 +33,7 @@ def add_segment(self, segment):
             return self._segments.get(segment.category)
 
     def __repr__(self):
-        d = {'account': self.account, 'timestamp': self.timestamp, 'segments': self.segments}
+        d = {'account': self.account, 'update_timestamp': self.update_timestamp, 'segments': self.segments}
         return MODEL_REPR.format(self.__class__.__name__, d)