diff --git a/telegram/utils/validate.py b/telegram/utils/validate.py
index 834cf9b17..d8629750a 100644
--- a/telegram/utils/validate.py
+++ b/telegram/utils/validate.py
@@ -21,24 +21,6 @@
 
 from telegram.error import InvalidToken
 
-try:
-    type(basestring)
-except NameError:
-    basestring = str
-
-
-def validate_string(arg, name):
-    """
-    Validate a string argument. Raises a ValueError if `arg` is neither an
-    instance of basestring (Python 2) or str (Python 3) nor None.
-
-    Args:
-        arg (basestring): The value to be tested
-        name (str): The name of the argument, for the error message
-    """
-    if not isinstance(arg, basestring) and arg is not None:
-        raise ValueError(name + ' is not a string')
-
 
 def validate_token(token):
     """a very basic validation on token"""
diff --git a/tests/test_inputcontactmessagecontent.py b/tests/test_inputcontactmessagecontent.py
new file mode 100644
index 000000000..231759cfd
--- /dev/null
+++ b/tests/test_inputcontactmessagecontent.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python
+#
+# A library that provides a Python interface to the Telegram Bot API
+# Copyright (C) 2015-2016
+# Leandro Toledo de Souza <devs@python-telegram-bot.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see [http://www.gnu.org/licenses/].
+
+"""This module contains a object that represents Tests for Telegram
+InputContactMessageContent"""
+
+import sys
+
+if sys.version_info[0:2] == (2, 6):
+    import unittest2 as unittest
+else:
+    import unittest
+
+sys.path.append('.')
+
+import telegram
+from tests.base import BaseTest
+
+
+class InputContactMessageContentTest(BaseTest, unittest.TestCase):
+    """This object represents Tests for Telegram InputContactMessageContent."""
+
+    def setUp(self):
+        self.phone_number = 'phone number'
+        self.first_name = 'first name'
+        self.last_name = 'last name'
+
+        self.json_dict = {
+            'first_name': self.first_name,
+            'phone_number': self.phone_number,
+            'last_name': self.last_name,
+        }
+
+    def test_icmc_de_json(self):
+        icmc = telegram.InputContactMessageContent.de_json(self.json_dict)
+
+        self.assertEqual(icmc.first_name, self.first_name)
+        self.assertEqual(icmc.phone_number, self.phone_number)
+        self.assertEqual(icmc.last_name, self.last_name)
+
+    def test_icmc_de_json_factory(self):
+        icmc = telegram.InputMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(isinstance(icmc, telegram.InputContactMessageContent))
+
+    def test_icmc_de_json_factory_without_required_args(self):
+        json_dict = self.json_dict
+
+        del (json_dict['phone_number'])
+        del (json_dict['first_name'])
+
+        icmc = telegram.InputMessageContent.de_json(json_dict)
+
+        self.assertFalse(icmc)
+
+    def test_icmc_to_json(self):
+        icmc = telegram.InputContactMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(self.is_json(icmc.to_json()))
+
+    def test_icmc_to_dict(self):
+        icmc = telegram.InputContactMessageContent.de_json(
+            self.json_dict).to_dict()
+
+        self.assertTrue(self.is_dict(icmc))
+        self.assertDictEqual(self.json_dict, icmc)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tests/test_inputlocationmessagecontent.py b/tests/test_inputlocationmessagecontent.py
new file mode 100644
index 000000000..fed6e4136
--- /dev/null
+++ b/tests/test_inputlocationmessagecontent.py
@@ -0,0 +1,83 @@
+#!/usr/bin/env python
+#
+# A library that provides a Python interface to the Telegram Bot API
+# Copyright (C) 2015-2016
+# Leandro Toledo de Souza <devs@python-telegram-bot.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see [http://www.gnu.org/licenses/].
+
+"""This module contains a object that represents Tests for Telegram
+InputLocationMessageContent"""
+
+import sys
+
+if sys.version_info[0:2] == (2, 6):
+    import unittest2 as unittest
+else:
+    import unittest
+
+sys.path.append('.')
+
+import telegram
+from tests.base import BaseTest
+
+
+class InputLocationMessageContentTest(BaseTest, unittest.TestCase):
+    """This object represents Tests for Telegram InputLocationMessageContent."""
+
+    def setUp(self):
+        self.latitude = 1.
+        self.longitude = 2.
+
+        self.json_dict = {
+            'longitude': self.longitude,
+            'latitude': self.latitude,
+        }
+
+    def test_ilmc_de_json(self):
+        ilmc = telegram.InputLocationMessageContent.de_json(self.json_dict)
+
+        self.assertEqual(ilmc.longitude, self.longitude)
+        self.assertEqual(ilmc.latitude, self.latitude)
+
+    def test_ilmc_de_json_factory(self):
+        ilmc = telegram.InputMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(isinstance(ilmc, telegram.InputLocationMessageContent))
+
+    def test_ilmc_de_json_factory_without_required_args(self):
+        json_dict = self.json_dict
+
+        del (json_dict['longitude'])
+        del (json_dict['latitude'])
+
+        ilmc = telegram.InputMessageContent.de_json(json_dict)
+
+        self.assertFalse(ilmc)
+
+    def test_ilmc_to_json(self):
+        ilmc = telegram.InputLocationMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(self.is_json(ilmc.to_json()))
+
+    def test_ilmc_to_dict(self):
+        ilmc = telegram.InputLocationMessageContent.de_json(
+            self.json_dict).to_dict()
+
+        self.assertTrue(self.is_dict(ilmc))
+        self.assertDictEqual(self.json_dict, ilmc)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tests/test_inputmessagecontent.py b/tests/test_inputmessagecontent.py
new file mode 100644
index 000000000..11e303fb2
--- /dev/null
+++ b/tests/test_inputmessagecontent.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env python
+#
+# A library that provides a Python interface to the Telegram Bot API
+# Copyright (C) 2015-2016
+# Leandro Toledo de Souza <devs@python-telegram-bot.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see [http://www.gnu.org/licenses/].
+
+"""This module contains a object that represents Tests for Telegram
+InputMessageContent"""
+
+import sys
+
+if sys.version_info[0:2] == (2, 6):
+    import unittest2 as unittest
+else:
+    import unittest
+
+sys.path.append('.')
+
+import telegram
+from tests.base import BaseTest
+
+
+class InputMessageContentTest(BaseTest, unittest.TestCase):
+    """This object represents Tests for Telegram InputMessageContent."""
+
+    def test_imc_de_json(self):
+        imc = telegram.InputMessageContent.de_json(None)
+
+        self.assertFalse(imc)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tests/test_inputtextmessagecontent.py b/tests/test_inputtextmessagecontent.py
new file mode 100644
index 000000000..b34536fe2
--- /dev/null
+++ b/tests/test_inputtextmessagecontent.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python
+#
+# A library that provides a Python interface to the Telegram Bot API
+# Copyright (C) 2015-2016
+# Leandro Toledo de Souza <devs@python-telegram-bot.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see [http://www.gnu.org/licenses/].
+
+"""This module contains a object that represents Tests for Telegram
+InputTextMessageContent"""
+
+import sys
+
+if sys.version_info[0:2] == (2, 6):
+    import unittest2 as unittest
+else:
+    import unittest
+
+sys.path.append('.')
+
+import telegram
+from tests.base import BaseTest
+
+
+class InputTextMessageContentTest(BaseTest, unittest.TestCase):
+    """This object represents Tests for Telegram InputTextMessageContent."""
+
+    def setUp(self):
+        self.message_text = '*message text*'
+        self.parse_mode = telegram.ParseMode.MARKDOWN
+        self.disable_web_page_preview = True
+
+        self.json_dict = {
+            'parse_mode': self.parse_mode,
+            'message_text': self.message_text,
+            'disable_web_page_preview': self.disable_web_page_preview,
+        }
+
+    def test_itmc_de_json(self):
+        itmc = telegram.InputTextMessageContent.de_json(self.json_dict)
+
+        self.assertEqual(itmc.parse_mode, self.parse_mode)
+        self.assertEqual(itmc.message_text, self.message_text)
+        self.assertEqual(itmc.disable_web_page_preview,
+                         self.disable_web_page_preview)
+
+    def test_itmc_de_json_factory(self):
+        itmc = telegram.InputMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(isinstance(itmc, telegram.InputTextMessageContent))
+
+    def test_itmc_de_json_factory_without_required_args(self):
+        json_dict = self.json_dict
+
+        del (json_dict['message_text'])
+
+        itmc = telegram.InputMessageContent.de_json(json_dict)
+
+        self.assertFalse(itmc)
+
+    def test_itmc_to_json(self):
+        itmc = telegram.InputTextMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(self.is_json(itmc.to_json()))
+
+    def test_itmc_to_dict(self):
+        itmc = telegram.InputTextMessageContent.de_json(
+            self.json_dict).to_dict()
+
+        self.assertTrue(self.is_dict(itmc))
+        self.assertDictEqual(self.json_dict, itmc)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/tests/test_inputvenuemessagecontent.py b/tests/test_inputvenuemessagecontent.py
new file mode 100644
index 000000000..ad37e0e3f
--- /dev/null
+++ b/tests/test_inputvenuemessagecontent.py
@@ -0,0 +1,94 @@
+#!/usr/bin/env python
+#
+# A library that provides a Python interface to the Telegram Bot API
+# Copyright (C) 2015-2016
+# Leandro Toledo de Souza <devs@python-telegram-bot.org>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see [http://www.gnu.org/licenses/].
+
+"""This module contains a object that represents Tests for Telegram
+InputVenueMessageContent"""
+
+import sys
+
+if sys.version_info[0:2] == (2, 6):
+    import unittest2 as unittest
+else:
+    import unittest
+
+sys.path.append('.')
+
+import telegram
+from tests.base import BaseTest
+
+
+class InputVenueMessageContentTest(BaseTest, unittest.TestCase):
+    """This object represents Tests for Telegram InputVenueMessageContent."""
+
+    def setUp(self):
+        self.latitude = 1.
+        self.longitude = 2.
+        self.title = 'title'
+        self._address = 'address'  # nose binds self.address for testing
+        self.foursquare_id = 'foursquare id'
+
+        self.json_dict = {
+            'longitude': self.longitude,
+            'latitude': self.latitude,
+            'title': self.title,
+            'address': self._address,
+            'foursquare_id': self.foursquare_id,
+        }
+
+    def test_ivmc_de_json(self):
+        ivmc = telegram.InputVenueMessageContent.de_json(self.json_dict)
+
+        self.assertEqual(ivmc.longitude, self.longitude)
+        self.assertEqual(ivmc.latitude, self.latitude)
+        self.assertEqual(ivmc.title, self.title)
+        self.assertEqual(ivmc.address, self._address)
+        self.assertEqual(ivmc.foursquare_id, self.foursquare_id)
+
+    def test_ivmc_de_json_factory(self):
+        ivmc = telegram.InputMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(isinstance(ivmc, telegram.InputVenueMessageContent))
+
+    def test_ivmc_de_json_factory_without_required_args(self):
+        json_dict = self.json_dict
+
+        del (json_dict['longitude'])
+        del (json_dict['latitude'])
+        del (json_dict['title'])
+        del (json_dict['address'])
+
+        ivmc = telegram.InputMessageContent.de_json(json_dict)
+
+        self.assertFalse(ivmc)
+
+    def test_ivmc_to_json(self):
+        ivmc = telegram.InputVenueMessageContent.de_json(self.json_dict)
+
+        self.assertTrue(self.is_json(ivmc.to_json()))
+
+    def test_ivmc_to_dict(self):
+        ivmc = telegram.InputVenueMessageContent.de_json(
+            self.json_dict).to_dict()
+
+        self.assertTrue(self.is_dict(ivmc))
+        self.assertDictEqual(self.json_dict, ivmc)
+
+
+if __name__ == '__main__':
+    unittest.main()