Add CustomizeSessions page

docs/source/index.rst

@@ -89,6 +89,7 @@ To get started, press the Next button.
     resources/AutoAuthorization
     resources/TextFormatting
     resources/BotsInteraction
+    resources/CustomizeSessions
     resources/ErrorHandling
 
 .. toctree::

docs/source/resources/CustomizeSessions.rst

@@ -0,0 +1,68 @@
+Customize Sessions
+==================
+
+As you may probably know, Telegram allows Users (and Bots) having more than one session (authorizations) registered
+in the system at the same time.
+
+Briefly explaining, sessions are simply new logins in your account and can be reviewed in the settings of an official
+app or by invoking `GetAuthorizations <../functions/account/GetAuthorizations>`_ with Pyrogram.
+
+
+.. figure:: https://i.imgur.com/lzGPCdZ.png
+    :width: 70%
+    :align: center
+
+    A Pyrogram session running on Linux, Python 3.6.
+
+That's how a session looks like on the Android app, showing the three main pieces of information.
+
+-   ``app_version``: **Pyrogram 🔥 0.7.5**
+-   ``device_model``: **CPython 3.6.5**
+-   ``system_version``: **Linux 4.15.0-23-generic**
+
+Set Custom Values
+-----------------
+
+To set custom values, you can either make use of the ``config.ini`` file, this way:
+
+.. code-block:: ini
+
+    [pyrogram]
+    app_version = 1.2.3
+    device_model = PC
+    system_version = Linux
+
+Or, pass the arguments directly in the Client's constructor.
+
+.. code-block:: python
+
+    app = Client(
+        "my_account",
+        app_version="1.2.3",
+        device_model="PC",
+        system_version="Linux"
+    )
+
+Set Custom Languages
+--------------------
+
+These are two extra parameters you can change: ``system_lang_code`` (OS language) and ``lang_code`` (Client language).
+They exist to tell Telegram in which language it should speak to you (terms of service, service messages, ...) and are
+usually both set to the same value, in `ISO 639-1 <https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes>`_ standard.
+Pyrogram uses "en" (English) for both by default.
+
+With the following code we make Telegram know we want it to speak in Italian (it):
+
+.. code-block:: ini
+
+    [pyrogram]
+    system_lang_code = it
+    lang_code = it
+
+.. code-block:: python
+
+    app = Client(
+        "my_account",
+        system_lang_code="it",
+        lang_code="it",
+    )