lsof(8) -c python -u user
list open files
-c c     This  option  selects  the listing of files for processes executing the command that begins with
         the characters of c.  Multiple commands may be specified, using multiple -c options.   They  are
         joined in a single ORed set before participating in AND option selection.

                If c begins with a '^', then the following characters specify a command name whose processes are
                to be ignored (excluded.)

                If c begins and ends with a slash ('/'), the characters between the slashes are interpreted as a
                regular  expression.   Shell meta-characters in the regular expression must be quoted to prevent
                their interpretation by the shell.  The closing slash may be followed by these modifiers:

                     b    the regular expression is a basic one.
                     i    ignore the case of letters.
                     x    the regular expression is an extended one
                          (default).

                See the lsof FAQ (The FAQ section gives its  location.)   for  more  information  on  basic  and
                extended regular expressions.

                The  simple  command  specification  is  tested  first.  If that test fails, the command regular
                expression is applied.  If the simple command test succeeds, the command regular expression test
                isn't  made.   This may result in ``no command found for regex:'' messages when lsof's -V option
                is specified.
-u s     This option selects the listing of files for the user whose login names or user ID  numbers  are
         in  the  comma-separated  set s - e.g., ``abe'', or ``548,root''.  (There should be no spaces in
         the set.)

         Multiple login names or user ID numbers are joined in a single ORed set before participating  in
         AND option selection.

         If  a  login  name  or  user  ID  is  preceded  by a `^', it becomes a negation - i.e., files of
         processes owned by the login name or user ID will never be listed.  A negated login name or user
         ID  selection  is  neither  ANDed nor ORed with other selections; it is applied before all other
         selections and absolutely excludes the listing of the files of the  process.   For  example,  to
         direct  lsof to exclude the listing of files belonging to root processes, specify ``-u^root'' or
         ``-u^0''.
source manpages: lsof