Django error :TypeError: Object of type CharField is not JSON serializable.Thanks in Advance

Question

**models.py**

from django.db import models
class Identity(models.Model):
    first_name=models.CharField(max_length=40,null=True,blank=False),
    last_name=models.CharField(max_length=40,null=True,blank=False),
    def __str__ (self):
        return self.first_name

**serializers.py**

from rest_framework import serializers
from .models import Identity

class IdentitySerializer(serializers.ModelSerializer):
    class Meta:
        model = Identity
        fields=('first_name','last_name',)



**views.py**
from rest_framework import generics
from .models import Identity
from .serializers import IdentitySerializer

class IdentityList(generics.ListCreateAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer

class Identity(generics.RetrieveUpdateDestroyAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer
   
**Application** **urls.py**
from django.urls import path,include;
from App import views

urlpatterns = [
    path('identity', views.IdentityList.as_view()),
    path('<int:ik>/', views.Identity.as_view()),
]

**Project** **urls.py**


from django.contrib import admin
from django.urls import path, include
from rest_framework.schemas import get_schema_view 
from django.views.generic import TemplateView

urlpatterns = [
    path('', include('App.urls')),
    #path('', admin.site.urls),
    path('openapi', get_schema_view(
        title="Service",
        description="API development"
    ), name='openapi-schema'),
     path('docs/', TemplateView.as_view(
        template_name='documentation.html',
        extra_context={'schema_url':'openapi-schema'}
    ), name='swagger-ui'),

]

**setting.py**

"""
Django settings for solutionOne project.

Generated by 'django-admin startproject' using Django 4.0.4.

For more information on this file, see
https://docs.djangoproject.com/en/4.0/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/4.0/ref/settings/
"""

from pathlib import Path

# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/4.0/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'django-insecure-72^br23d)5w=bk6q_7s)88u)ld!9yrpwzyv*vsn5qmpbts(_m-'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'App',
    'rest_framework', 
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'solutionOne.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'solutionOne.wsgi.application'


# Database
# https://docs.djangoproject.com/en/4.0/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}


# Password validation
# https://docs.djangoproject.com/en/4.0/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/4.0/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/4.0/howto/static-files/

STATIC_URL = 'static/'

# Default primary key field type
# https://docs.djangoproject.com/en/4.0/ref/settings/#default-auto-field

DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'

''' error: models.py

from django.db import models
class Identity(models.Model):
    first_name=models.CharField(max_length=40,null=True,blank=False),
    last_name=models.CharField(max_length=40,null=True,blank=False),
    def __str__ (self):
        return self.first_name

**serializers.py**

from rest_framework import serializers
from .models import Identity

class IdentitySerializer(serializers.ModelSerializer):
    class Meta:
        model = Identity
        fields=('first_name','last_name',)



**views.py**
from rest_framework import generics
from .models import Identity
from .serializers import IdentitySerializer

class IdentityList(generics.ListCreateAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer

class Identity(generics.RetrieveUpdateDestroyAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer
   
**Application** **urls.py**
from django.urls import path,include;
from App import views

urlpatterns = [
    path('identity', views.IdentityList.as_view()),
    path('<int:ik>/', views.Identity.as_view()),
]

**Project** **urls.py**


from django.contrib import admin
from django.urls import path, include
from rest_framework.schemas import get_schema_view 
from django.views.generic import TemplateView

urlpatterns = [
    path('', include('App.urls')),
    #path('', admin.site.urls),
    path('openapi', get_schema_view(
        title="Service",
        description="API development"
    ), name='openapi-schema'),
     path('docs/', TemplateView.as_view(
        template_name='documentation.html',
        extra_context={'schema_url':'openapi-schema'}
    ), name='swagger-ui'),

]

**setting.py**

"""
Django settings for solutionOne project.

Generated by 'django-admin startproject' using Django 4.0.4.

For more information on this file, see
https://docs.djangoproject.com/en/4.0/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/4.0/ref/settings/
"""

from pathlib import Path

# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/4.0/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'django-insecure-72^br23d)5w=bk6q_7s)88u)ld!9yrpwzyv*vsn5qmpbts(_m-'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'App',
    'rest_framework', 
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'solutionOne.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'solutionOne.wsgi.application'


# Database
# https://docs.djangoproject.com/en/4.0/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}


# Password validation
# https://docs.djangoproject.com/en/4.0/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/4.0/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/4.0/howto/static-files/

STATIC_URL = 'static/'

# Default primary key field type
# https://docs.djangoproject.com/en/4.0/ref/settings/#default-auto-field

DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'


**models.py**

from django.db import models
class Identity(models.Model):
    first_name=models.CharField(max_length=40,null=True,blank=False),
    last_name=models.CharField(max_length=40,null=True,blank=False),
    def __str__ (self):
        return self.first_name

**serializers.py**

from rest_framework import serializers
from .models import Identity

class IdentitySerializer(serializers.ModelSerializer):
    class Meta:
        model = Identity
        fields=('first_name','last_name',)



**views.py**
from rest_framework import generics
from .models import Identity
from .serializers import IdentitySerializer

class IdentityList(generics.ListCreateAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer

class Identity(generics.RetrieveUpdateDestroyAPIView):
    queryset=Identity.objects.all()
    serializer_class=IdentitySerializer
   
**Application** **urls.py**
from django.urls import path,include;
from App import views

urlpatterns = [
    path('identity', views.IdentityList.as_view()),
    path('<int:ik>/', views.Identity.as_view()),
]

**Project** **urls.py**


from django.contrib import admin
from django.urls import path, include
from rest_framework.schemas import get_schema_view 
from django.views.generic import TemplateView

urlpatterns = [
    path('', include('App.urls')),
    #path('', admin.site.urls),
    path('openapi', get_schema_view(
        title="Service",
        description="API development"
    ), name='openapi-schema'),
     path('docs/', TemplateView.as_view(
        template_name='documentation.html',
        extra_context={'schema_url':'openapi-schema'}
    ), name='swagger-ui'),

]

**setting.py**

"""
Django settings for solutionOne project.

Generated by 'django-admin startproject' using Django 4.0.4.

For more information on this file, see
https://docs.djangoproject.com/en/4.0/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/4.0/ref/settings/
"""

from pathlib import Path

# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/4.0/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'django-insecure-72^br23d)5w=bk6q_7s)88u)ld!9yrpwzyv*vsn5qmpbts(_m-'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'App',
    'rest_framework', 
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'solutionOne.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'solutionOne.wsgi.application'


# Database
# https://docs.djangoproject.com/en/4.0/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}


# Password validation
# https://docs.djangoproject.com/en/4.0/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/4.0/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/4.0/howto/static-files/

STATIC_URL = 'static/'

# Default primary key field type
# https://docs.djangoproject.com/en/4.0/ref/settings/#default-auto-field

DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'

'''

Answer 1

In your serializer instead you can try this

class IdentitySerializer(serializers.ModelSerializer):
    class Meta:
        model = Identity
        fields='__all__'