provides categories of errors, which are named after the common HTTP errors and are subclass-ed from the RPCError:

In case Pyrogram does not know anything about a specific error yet, it raises a generic error from its known category,

for example, an unknown error with error code ``400``, will be raised as a ``BadRequest``. This way you can catch the

whole category of errors and be sure to also handle these unknown errors.

In case a whole class of errors is unknown (that is, an error code that is unknown), Pyrogram will raise a special

``520 UnknownError`` exception.

In both cases, Pyrogram will log them in the ``unknown_errors.txt`` file. Users are invited to report

these unknown errors in the `discussion group <https://t.me/pyrogram>`_.

have to wait before you can try again, some other errors contain the DC number on which the request must be repeated on.

The value is stored in the ``x`` attribute of the exception object: