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+The first parameter you pass the the constructor of the `TelegramClient` is the `session`, and defaults to be the session name (or full path). That is, if you create a `TelegramClient('anon')` instance and connect, an `anon.session` file will be created on the working directory.
+
+These sessions contain the required information to talk to the Telegram servers, such as to which IP the client should connect, port, authorization key so that messages can be encrypted, and so on.
+
+These files will by default also save all the input entities that you've seen (**WIP**).
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