I compiled Emacs from source. However I see that comint behaves different
in run-scheme vs run-python. In Python, the ">>>" prompt doesn't get
deleted when you do backspace, however in Scheme the "=>" prompt is
deletable.

Is there a reason why different REPL's would behave differently in
comint-mode?  I also notice that except ">>>" any other text in run-python
is deletable. Can you please make this uniform?

--text follows this line--

In GNU Emacs 25.0.50.2 (i686-pc-linux-gnu, GTK+ Version 3.10.8)
 of 2015-07-22 on lpt-tnishant
Repository revision: fa1463896d5048e0e43a9b55db1ed82c6441e693
Windowing system distributor `The X.Org Foundation', version 11.0.11501000
System Description:    Linux Mint 17.1 Rebecca

Configured features:
XPM JPEG TIFF GIF PNG SOUND GSETTINGS NOTIFY GNUTLS LIBXML2 FREETYPE XFT
ZLIB TOOLKIT_SCROLL_BARS GTK3 X11

Important settings:
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  locale-coding-system: iso-latin-1-unix

Major mode: EMMS

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Playback channels: 88%
funcall-interactively: Buffer is read-only: #<buffer  *EMMS Playlist*>
Playback channels: 86%
(No changes need to be saved)
progn: Beginning of buffer
Shell native completion is enabled.
delete-backward-char: Text is read-only [4 times]
Quit [3 times]
Buffer "*scheme*" has a running process; kill it? (y or n) y
Overwrite mode enabled in current buffer

Load-path shadows:
~/.emacs.d/elisp/emms/lisp/tq hides
/usr/local/share/emacs/25.0.50/lisp/emacs-lisp/tq

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Memory information:
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