Is 'print' key word? How to describe this shell command with string of python?

Question

Some error are reported, when format string that is a shell command.

The python code:

str = "jps | grep {0} | grep -v {1} | awk '{print $1}' | xargs kill -9".format(1,2)

The error information:

Traceback (most recent call last):
File "<stdin>", line 1, in <module> KeyError: 'print'

How to fix it?

score 2 · Answer 1 · answered Apr 18 '17 at 12:48

2

Use:

>>> "jps | grep {0} | grep -v {1} | awk '{{print $1}}' | xargs kill -9".format(1,2)
"jps | grep 1 | grep -v 2 | awk '{print $1}' | xargs kill -9"

answered Apr 18 '17 at 12:48

donkopotamus

score 1 · Answer 2 · answered Apr 18 '17 at 12:50

Answering the title

In Python 2.7, print is a keyword. In Python 3.x, it is not.

"jps | grep {0} | grep -v {1} | awk '{{print $1}}' | xargs kill -9".format(1,2)

When you wrap a value inside of extra {} in format, it will interpret the string literally, not trying to replace it.