note: no other Python-related emacs packages are being used;
only the builtin one.

1. create new file "test.py" with following:

def f(x):
    return x+1

2. C-c C-p to run-python

3. place point immediately after "return x+1"

4. C-M-x for python-shell-send-defun

result:

    SyntaxError: 'return' outside function

it appears that only one line is being sent, instead of both lines.



In GNU Emacs 25.3.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version
10.9.5 (Build 13F1911))
 of 2017-09-12 built on builder10-9.local
Windowing system distributor 'Apple', version 10.3.1561
Configured using:
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Configured features:
NOTIFY ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS NS MODULES

Important settings:
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Major mode: Python

Minor modes in effect:
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Recent messages:
uncompressing python.el.gz...done
Making completion list...
t

delete-backward-char: Text is read-only
Quit

<C-tab> is undefined
mouse-2, RET: find function's definition
uncompressing python.el.gz...done

Load-path shadows:
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Memory information:
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