diff --git a/.idea/misc.xml b/.idea/misc.xml
index 6ba69809..bcbff53b 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,4 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.9 (unicoding)" project-jdk-type="Python SDK" />
+  <component name="PyCharmProfessionalAdvertiser">
+    <option name="shown" value="true" />
+  </component>
 </project>
\ No newline at end of file
diff --git a/accounting/api/account.py b/accounting/api/account.py
index e843e616..f9bc154d 100644
--- a/accounting/api/account.py
+++ b/accounting/api/account.py
@@ -6,6 +6,7 @@
 from typing import List
 from django.db.models import Sum, Avg
 from rest_framework import status
+import mptt
 
 from restauth.authorization import AuthBearer
 
@@ -60,17 +61,15 @@ def get_account_balances(request):
 
 
 class Balance:
-    def __init__(self, balances):
-        balance1 = balances[0]
-        balance2 = balances[1]
-
-        if balance1['currency'] == 'USD':
-            balanceUSD = balance1['sum']
-            balanceIQD = balance2['sum']
-        else:
-            balanceIQD = balance1['sum']
-            balanceUSD = balance2['sum']
 
+    def __init__(self, balances):
+        balanceIQD = 0
+        balanceUSD = 0
+        for i in balances:
+            if i['currency'] == 'USD':
+                balanceUSD = i['sum']
+            if i['currency'] == 'IQD':
+                balanceIQD = i['sum']
         self.balanceUSD = balanceUSD
         self.balanceIQD = balanceIQD
 
@@ -85,3 +84,8 @@ def __add__(self, other):
             'sum': self.balanceIQD
         }]
 
+    def __radd__(self,other):
+        if other == 0:
+            return self
+        else:
+            return self.__add__(other)
diff --git a/accounting/migrations/0007_account_level_account_lft_account_rght_and_more.py b/accounting/migrations/0007_account_level_account_lft_account_rght_and_more.py
new file mode 100644
index 00000000..9b190705
--- /dev/null
+++ b/accounting/migrations/0007_account_level_account_lft_account_rght_and_more.py
@@ -0,0 +1,44 @@
+# Generated by Django 4.0.6 on 2022-08-03 14:02
+
+from django.db import migrations, models
+import django.db.models.deletion
+import mptt.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('accounting', '0006_alter_account_code_alter_account_full_code_and_more'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='account',
+            name='level',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='account',
+            name='lft',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='account',
+            name='rght',
+            field=models.PositiveIntegerField(default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='account',
+            name='tree_id',
+            field=models.PositiveIntegerField(db_index=True, default=0, editable=False),
+            preserve_default=False,
+        ),
+        migrations.AlterField(
+            model_name='account',
+            name='parent',
+            field=mptt.fields.TreeForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, to='accounting.account'),
+        ),
+    ]
diff --git a/accounting/models.py b/accounting/models.py
index a7d49b7f..6bd3f006 100644
--- a/accounting/models.py
+++ b/accounting/models.py
@@ -3,6 +3,11 @@
 from django.dispatch import receiver
 from django.db.models.signals import post_save
 from accounting.exceptions import AccountingEquationError
+from mptt.models import TreeForeignKey,MPTTModel
+from mptt.fields import TreeForeignKey
+from django.shortcuts import get_object_or_404
+
+
 
 '''
 
@@ -48,8 +53,8 @@ class CurrencyChoices(models.TextChoices):
     IQD = 'IQD', 'IQD'
 
 
-class Account(models.Model):
-    parent = models.ForeignKey('self', null=True, blank=True, on_delete=models.SET_NULL)
+class Account(MPTTModel):
+    parent = TreeForeignKey('self', null=True, blank=True, on_delete=models.SET_NULL)
     type = models.CharField(max_length=255, choices=AccountTypeChoices.choices)
     name = models.CharField(max_length=255)
     code = models.CharField(max_length=20, null=True, blank=True)
@@ -60,7 +65,16 @@ def __str__(self):
         return f'{self.full_code} - {self.name}'
 
     def balance(self):
-        return self.journal_entries.values('currency').annotate(sum=Sum('amount')).order_by()
+        result = [
+            account.journal_entries.values('currency').annotate(sum=Sum('amount')).order_by()
+            for account in self.get_descendants(include_self=False)
+
+        ]
+        return result
+
+
+
+        #return self.journal_entries.values('currency').annotate(sum=Sum('amount')).order_by()
 
     # def save(
     #         self, force_insert=False, force_update=False, using=None, update_fields=None
diff --git a/db.sqlite3 b/db.sqlite3
index 3cb73d59..88301b72 100644
Binary files a/db.sqlite3 and b/db.sqlite3 differ
diff --git a/task4.py b/task4.py
new file mode 100644
index 00000000..05dbbb44
--- /dev/null
+++ b/task4.py
@@ -0,0 +1,28 @@
+iqd = 50
+usd = 40
+def __gt__(self, other):
+    IQD = bool(self.balanceiqd > other.balanceIQD)
+    USD = bool(self.balanceUSD > other.balanceUSD)
+    return IQD, USD
+
+
+def __lt__(self, other):
+    IQD = bool(self.balanceiqd < other.balanceIQD)
+    USD = bool(self.balanceUSD < other.balanceUSD)
+    return IQD, USD
+
+
+def other_than_gt_and_ls(self, other):
+    if self.balanceIQD > other.balanceIQD and self.balanceUSD < other.balanceUSD:
+        return True, False
+    else:
+        return False, True
+
+
+def is_zero(self):
+    if self.balanceIQD == 0 and self.balanceUSD == 0:
+        return True
+    else:
+        return False
+
+print(iqd.__lt__(50))
\ No newline at end of file