fix: cache_key mpoint保留

apps/enm/models.py

@@ -43,7 +43,9 @@ class Mpoint(CommonBModel):
     need_display = models.BooleanField("是否需要展示", default=False)
     report_sortstr = models.CharField('在报告中的排序', max_length=50, default='', blank=True)
 
-
+    @classmethod
+    def cache_key(cls, code: str):
+        return f"mpoint_{code}"
 class MpLogx(models.Model):
     """
     测点记录超表

apps/enm/services.py

@@ -119,7 +119,7 @@ class MpointCache:
     """
     def __init__(self, code: str):
         self.code = code 
-        self.cache_key = f'mpoint_{code}'
+        self.cache_key = Mpoint.cache_key(code)
         self.data = self.get()
     
     def get(self, force_update=False, update_mplogx=True):