Checklist

• I am sure the error is coming from Pyrogram's code and not elsewhere.
• I have searched in the issue tracker for similar bug reports, including closed ones.
• I ran pip3 install -U https://github.com/pyrogram/pyrogram/archive/develop.zip and reproduced the issue using the latest development version.

Description

Deprecation warning due to invalid escape sequences. Using raw strings or escaping them again helps in resolving this. Check https://github.com/asottile/pyupgrade/ for automatic fix of this.

Steps to Reproduce

find . -iname '*.py' | grep -Ev 'rdf4|tool' | xargs -P4 -I{} python3.8 -Wall -m py_compile {}
./compiler/api/compiler.py:29: DeprecationWarning: invalid escape sequence \w
  ARGS_RE = re.compile("[^{](\w+):([\w?!.<>#]+)")
./compiler/api/compiler.py:318: DeprecationWarning: invalid escape sequence \.
  re.sub("Optional\. ", "", docs[i].split("§")[1].rstrip(".") + ".")
./pyrogram/client/client.py:1759: DeprecationWarning: invalid escape sequence \*
  """Upload a file onto Telegram servers, without actually sending the message to anyone.
./pyrogram/client/types/messages_and_media/message.py:776: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_animation* :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:918: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_audio* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:1270: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_document* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:1671: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_photo* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:1869: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_sticker* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:2079: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_video* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:2222: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_video_note* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:2345: DeprecationWarning: invalid escape sequence \*
  """Bound method *reply_voice* of :obj:`Message`.
./pyrogram/client/types/messages_and_media/message.py:2993: DeprecationWarning: invalid escape sequence \*
  """Bound method *download* of :obj:`Message`.
./pyrogram/client/methods/messages/send_sticker.py:46: DeprecationWarning: invalid escape sequence \*
  """Send static .webp or animated .tgs stickers.
./pyrogram/client/methods/messages/send_voice.py:49: DeprecationWarning: invalid escape sequence \*
  """Send audio files.
./pyrogram/client/methods/messages/download_media.py:44: DeprecationWarning: invalid escape sequence \*
  """Download the media from a message.
./pyrogram/client/methods/messages/send_document.py:49: DeprecationWarning: invalid escape sequence \*
  """Send generic files.
./pyrogram/client/methods/messages/send_video_note.py:49: DeprecationWarning: invalid escape sequence \*
  """Send video messages.
./pyrogram/client/methods/messages/send_video.py:53: DeprecationWarning: invalid escape sequence \*
  """Send video files.
./pyrogram/client/methods/messages/send_photo.py:49: DeprecationWarning: invalid escape sequence \*
  """Send photos.
./pyrogram/client/methods/messages/send_audio.py:52: DeprecationWarning: invalid escape sequence \*
  """Send audio files.
./pyrogram/client/methods/messages/send_animation.py:53: DeprecationWarning: invalid escape sequence \*
  """Send animation files (animation or H.264/MPEG-4 AVC video without sound).