diff --git a/przyrost/admin.py b/przyrost/admin.py
index 694323f..5615e7a 100644
--- a/przyrost/admin.py
+++ b/przyrost/admin.py
@@ -1 +1,7 @@
 from django.contrib import admin
+from django.contrib import admin
+from przyrost.models import *
+
+@admin.register(Category, Post, User, StaticPage, MenuEntry, Menu, Comment, Config)
+class AuthorAdmin(admin.ModelAdmin):
+    pass
\ No newline at end of file
diff --git a/przyrost/models.py b/przyrost/models.py
index 35bf51d..cf7209f 100644
--- a/przyrost/models.py
+++ b/przyrost/models.py
@@ -14,8 +14,15 @@ class Post(models.Model):
     authors=models.ManyToManyField(User)
     category = models.ForeignKey(Category, on_delete=models.CASCADE)
     @staticmethod
+    def getPostsOfAuthor(author):
+        return Post.objects.filter(authors=author)
+    @staticmethod
+    def getYesterday():
+        y=(datetime.datetime.today() - datetime.timedelta(days=1))
+        return Post.objects.filter(created_at__day=y.day, created_at__month=y.month, created_at__year=y.year)
+    @staticmethod
     def getTodays():
-        return Post.objects.filter(created_at=timezone.datetime.today())
+        return Post.objects.filter(created_at__day=datetime.datetime.now().date().day)
     @staticmethod
     def getPage(page:int):
         a = Post.objects.all()
diff --git a/przyrost/tests.py b/przyrost/tests.py
index b82cc18..b80a27b 100644
--- a/przyrost/tests.py
+++ b/przyrost/tests.py
@@ -1,6 +1,8 @@
 from django.test import TestCase
 from przyrost.models import *
 from django.utils import timezone
+from django.core import serializers
+
 class testbasic(TestCase):
 
     def setUp(self) -> None:
@@ -18,6 +20,52 @@ class testbasic(TestCase):
         )
         p.authors.set([u])
         p.save()
+
+        d = """[{"model": "przyrost.post","fields": {
+                   "text": "to jest drugi post",
+                   "category": 1, "authors": [1]}}]"""
+        obj = serializers.deserialize("json", d)
+        for l in obj:
+            if not l.object.created_at:
+                l.object.created_at = datetime.datetime.now()
+            l.save()
+
+        xml = """<?xml version="1.0" encoding="utf-8"?><django-objects version="1.0"><object model="przyrost.post" ><field name="text" type="TextField">Why would I use XML???</field><field name="created_at" type="DateTimeField">2012-12-01T14:02:01.589710</field><field name="category" rel="ManyToOneRel" to="przyrost.category">1</field><field name="authors" rel="ManyToManyRel" to="przyrost.user"><object pk="1"></object></field></object><object model="przyrost.post" pk="2"><field name="text" type="TextField">to jest drugi post</field><field name="created_at" type="DateTimeField">2019-12-08T13:52:18.473000</field><field name="category" rel="ManyToOneRel" to="przyrost.category">1</field><field name="authors" rel="ManyToManyRel" to="przyrost.user"><object pk="1"></object></field></object></django-objects>"""
+        obj = serializers.deserialize("xml", xml)
+        for l in obj:
+            if not l.object.created_at:
+                l.object.created_at = datetime.datetime.now()
+            l.save()
+
+
+        print("final values:")
+        print(Post.objects.all().values())
     def test_getPostByDate(self):
-        self.assertEqual(len(Post.objects.all()),1)
-        self.assertEqual(len(Post.getTodays()), 1)
+
+        print(list(Post.objects.all().values()))
+        self.assertEqual(len(Post.objects.all()),3)
+        self.assertEqual(len(Post.getTodays()), 2)
+        self.assertEqual(len(Post.getYesterday()), 0)
+    def test__serializeXML(self):
+        print("XML: ")
+        data = serializers.serialize("xml", Post.objects.all())
+        print(data)
+    def test__serializeJSON(self):
+        print("JSON: ")
+        data = serializers.serialize("json", Post.objects.all())
+        print(data)
+
+    def test__deserializeJSON(self):
+        d= """[{"model": "przyrost.post","fields": {
+            "text": "to jest drugi post",
+            "created_at": "2019-12-08T13:52:18.473", "category": 1, "authors": [1]}}]"""
+        obj = serializers.deserialize("json",d)
+        #for l in obj:
+        #    l.save()
+        # from time import sleep
+        #sleep(1)
+        print("new values")
+        print(Post.objects.all().values())
+    def test__getPostsOfAuthor(self):
+        d = Post.getPostsOfAuthor(User.objects.filter(name="Admin")[0])
+        self.assertEqual(len(d), 3)
\ No newline at end of file