change return statements to scalars

Add total month cost method to budget cat

app/models.py

@@ -1,7 +1,6 @@
 from app import db
 from sqlalchemy import Column, INTEGER, String, select
 import datetime
-
 class Vendor(db.Model):
     __tablename__ = 'vendor'
     id            = Column('id', INTEGER(), primary_key=True, autoincrement=True)
@@ -12,7 +11,7 @@ class Vendor(db.Model):
         return db.session.execute(select(BudgetCategory).where(BudgetCategory.id==self.bc_id)).scalar()
     
     def get_line_items(self):
-        return db.session.execute(select(LineItem).where(LineItem.vendor_id==self.id)).all()
+        return db.session.execute(select(LineItem).where(LineItem.vendor_id==self.id)).scalars().all()
     
     def __repr__(self) -> str:
         return f'{self.name}'
@@ -23,7 +22,7 @@ class BudgetCategory(db.Model):
     name          = Column('name', String(), nullable=False)
 
     def get_vendors(self):
-        return db.session.execute(select(Vendor).where(Vendor.bc_id==self.id)).all()
+        return db.session.execute(select(Vendor).where(Vendor.bc_id==self.id)).scalars().all()
 
     def get_line_items(self):
         line_items = []
@@ -32,6 +31,17 @@ class BudgetCategory(db.Model):
             line_items += vendor.get_line_items()
         return line_items
     
+    def get_total_month_cost(self, month:int, year:int):
+        from .utils import get_month_timestamps
+        first_ts, last_ts = get_month_timestamps(month, year)
+        lis = self.get_line_items()
+        requested_month_lis = 0
+        for li in lis:
+            if first_ts < li.date < last_ts:
+                requested_month_lis += li.amount
+        return requested_month_lis
+
+    
 class LineItem(db.Model):
     __tablename__       = 'line_item'
     id                  = Column('id', INTEGER(), primary_key=True, autoincrement=True)