Attempts

imap <c-j>d <c-r>=system(%)
imap <c-j>d <c-r>=system('c:\pro)
imap <c-j>d <c-r>=system('c:\programming/python/project/vim\ python/getDateTimeNow.py)<cr>
imap <c-j>d <c-r>=system('c:\programming/python/project/vim\ python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:\programming\python\project\vim/ pytho\/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:\programming\python\project\vim python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:\programming\python\project\vim python\getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project/vim python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project/vim\ python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project/vim// python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project/vim\\ python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project/vim/ python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:/programming/python/project//vim/ python/getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:\programming\python\project\vim\\ python\getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('c:\programming\python\project\\vim\ python\getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system('C:\Programming\Python\Project\Vim\ Python\getDateTimeNow.py')<cr>
imap <c-j>d <c-r>=system("C:\Programming\Python\Project\Vim\ Python\getDateTimeNow.py")<cr>
imap <c-j>d <c-r>=system("C:\\Programming\\Python\\Project\\Vim\ Python\\getDateTimeNow.py")<cr>
imap <c-j>d <c-r>=system("C:\\Programming\\Python\\Project\\Vim\\ Python\\getDateTimeNow.py")<cr>
set MYPATH=%
%
echo %
imap <c-j>d <c-r>=system("C:\\Programming\\Python\\Project\\Vim/ Python\\getDateTimeNow.py")<cr>
imap <c-j>d <c-r>=system("C:\Programming\Python\Project\Vim Python\getDateTimeNow.py")<cr>
imap <c-j>d <c-r>=system("%")<cr>
!echo %
read %
imap <c-j>d <c-r>=system("'")<cr>