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How do I strip space in the middle of output with python print

I am trying to create a bash script with python code.
I am running this code:
foo = raw_input("Hostname:")
print "imonitordb.pl -dumpEntityConfig 'device:",foo, "' | grep -v serviceNOC"
When I run the command, I get the following output:
imonitordb.pl -dumpEntityConfig 'device: monk ' | grep -v serviceNOC
I want to get ride of the spaces by monk so it reads:
imonitordb.pl -dumpEntityConfig 'device:monk' | grep -v serviceNOC
What am I missing?
I have tried to add
foo1 = foo.strip()
but that did not help.
I feel there is something really easy I am missing, just seeing if someone has a quick answer

As suggested by #game0ver, this is ideal:
print "imonitordb.pl -dumpEntityConfig 'device:{}' | grep -v serviceNOC".format(foo)
As suggested by #soon in comment this will also work:
print "imonitordb.pl -dumpEntityConfig 'device:" + foo + "' | grep -v serviceNOC"
Output:
imonitordb.pl -dumpEntityConfig 'device:monk' | grep -v serviceNOC

Execute a bash command with parameter in Python

This is a bash command that I run in python and get the expected result:
count = subprocess.Popen("ps -ef | grep app | wc -l", stdout=subprocess.PIPE, shell=True)
but when I'd like to pass an argument (count in this case) cannot figure out how to do it.
I tried:
pid = subprocess.call("ps -ef | grep app | awk -v n=' + str(count), 'NR==n | awk \'{print $2}\'", shell=True)
and
args = shlex.split('ps -ef | grep app | awk -v n=' + str(count), 'NR==n | awk \'{print $2}\'')
pid = subprocess.Popen(args, stdout=subprocess.PIPE, shell=True)
among other attempts, from various posts here, but still cannot make it.

You're mixing opening and closing quotations and you pass a colon by mistake on your other attempts among other things.
Try this for a fix:
pid = subprocess.call("ps -ef | grep app | awk -v n=" + str(count) + " NR==n | awk '{print $2}'", shell=True)
You opened the command parameter with " and there for you need to close it before you do + str() with a " and not a '. Further more i swapped the , 'NR= with + "NR= since you want to append more to your command and not pass a argument to subprocess.call().
As pointed out in the comments, there's no point in splitting the command with shlex since piping commands isn't implemented in subprocess, I would however like to point out that using shell=True is usually not recommended because for instance one of the examples given here.

An other vay is using format:
pid = subprocess.call("ps -ef | grep app | awk -v n={} NR==n | awk '{{print $2}}'".format(str(count)), shell=True)

Your Awk pipeline could be simplified a great deal - if the goal is to print the last match, ps -ef | awk '/app/ { p=$2 } END { print p }' does that. But many times, running Awk from Python is just silly, and performing the filtering in Python is convenient and easy, as well as obviously more efficient (you save not only the Awk process, but also the pesky shell=True).
for p in subprocess.check_output(['ps', '-ef']).split('\n'):
if 'app' in p:
pid = p.split()[1]

python subprocess output without \n

Here is a simple script running subprocess that retrieves IP from the ifconfig command output from the terminal.
I have noticed that subprocess.check_output() always returns a value with \n.
I desire to get a return value without \n.
How can this be done?
$ python
>>> import subprocess
>>> subprocess.check_output("ifconfig en0 | awk '{ print $2}' | grep -E -o '([0-9]{1,3}[\.]){3}[0-9]{1,3}'", shell=True)
'129.194.246.245\n'

For a generic way :
subprocess.check_output("echo hello world", shell=True).strip()

subprocess.check_output() does not add a newline. echo does. You can use the -n switch to suppress the newline, but you have to avoid using the shell built-in implementation (so use /bin/echo):
>>> import subprocess
>>> subprocess.check_output('/bin/echo -n hello world', shell=True)
'hello world'
If you use echo -n instead, you could get the string '-n hello world\n', as not all sh implementations support the -n switch support echo (OS X for example).
You could always use str.rstrip() or str.strip() to remove whitespace, of course, but don't blame subprocess here:
>>> subprocess.check_output('echo hello world', shell=True).rstrip('\n')
'hello world'
Your question update added a more complex example using awk and grep:
subprocess.check_output("ifconfig en0 | awk '{ print $2}' | grep -E -o '([0-9]{1,3}[\.]){3}[0-9]{1,3}'", shell=True)
Here grep adds the (final) newline. grep -o may print just the matching text, but still adds a newline to separate matches. See the grep manual:
-o
--only-matching
Print only the matched (non-empty) parts of matching lines, with each such part on a separate output line.
Emphasis mine.
You can add a tr -d '\n' at the end to remove any newlines from the output of your pipe:
>>> subprocess.check_output(
... "ifconfig en0 | awk '{ print $2}' | "
... "grep -E -o '([0-9]{1,3}[\.]){3}[0-9]{1,3}' | "
... "tr -d '\n'", shell=True)
'172.17.174.160'

You can str.rstrip any newline or use what Martijn suggests, you can also parse the output using python with the need to awk or grep which won't add any newlines:
You can split:
out = subprocess.check_output(["ifconfig", "en0"])
for line in out.splitlines():
if line.lstrip().startswith("inet "):
print(line.split()[1].split(":", 2)[1])
print(ip.search(line))
break
Or use your own regex:
import re
out = subprocess.check_output(["ifconfig", "en0"])
print(re.search('([0-9]{1,3}[\.]){3}[0-9]{1,3}', out).group())
The point being you don't need awk or grep.
If you want to match ipv4 or ipv6 and also catch when there is an error returned i.e no such interface you can catch a CalledProcessError which will be raised for any non zero exit status, it is easy use the regex for ipv4 but for ipv6 it is simpler to use inet6 to grab the ipv6 address.
from subprocess import check_output, CalledProcessError
import re
def get_ip(iface, ipv="ipv4"):
try:
out = check_output(["ifconfig", iface])
except CalledProcessError as e:
print(e.message)
return False
try:
if ipv == "ipv4":
return re.search('([0-9]{1,3}[\.]){3}[0-9]{1,3}', out).group()
return re.search("(?<=inet6 addr:)(.*?)(?=/)", out).group().lstrip()
except AttributeError as e:
print("No {} address for interface {}".format(ipv, iface))
return False
Demo:
In [2]: get_ip("wlan0")
Out[2]: '192.168.43.168'
In [3]: get_ip("wlan0","ipv6")
Out[3]: 'fe80::120b:a9ff:fe03:bb10'
In [4]: get_ip("wlan1","ipv6")
wlan1: error fetching interface information: Device not found
Out[4]: False

This is what you have :
$ python
>>> import subprocess
>>> subprocess.check_output("ifconfig eth0 | awk '{ print $2}' | grep -E -o '([0-9]{1,3}[\.]){3}[0-9]{1,3}'", shell=True)
'172.31.94.116\n'
Try this instead :
$ python
>>> import subprocess
>>> subprocess.check_output("ifconfig eth0 | awk '{ print $2}' | grep -E -o '([0-9]{1,3}[\.]){3}[0-9]{1,3}'", shell=True).strip()
'172.31.94.116'

How to split up the command here for using subprocess.Popen()

ip = subprocess.Popen(["/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') | grep \"inet addr\" | awk -F: '{print $2}' | awk \'{print $1}\'"], stdout=subprocess.PIPE)
I am not sure where to put the commas to separate them to use this command using subprocess.Popen. Does anyone know?

You are using shell features (the pipe) so instead of splitting the command, you should pass it as a single string (not a list) with shell=True
ip = subprocess.Popen("/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') | grep \"inet addr\" | awk -F: '{print $2}' | awk \'{print $1}\'",
shell=True,
stdout=subprocess.PIPE)

Here's what I would recommend.
Create a file with this contents - call it 'route-info' and make it executable:
#!/bin/sh
/sbin/ifconfig $(/sbin/route | awk '/default/ {print $8}') |
grep "inet addr" |
awk -F: '{print $2}' |
awk '{print $1}'
In your python program, use:
ip = subprocess.Popen(["/path/to/route-info"], stdout=subprocess.PIPE)
Then you don't have to worry about quoting characters and you can independently test the route-info script to make sure it is working correctly.
The script route-info doesn't take any command line arguments, but if it did this is how you would pass them:
ip = subprocess.Popen(["/path/to/route-info", arg1, arg2, ...], stdout=subprocess.PIPE)

Quoting the official documentation of subprocess.Popen here
It may not be obvious how to break a shell command into a sequence of
arguments, especially in complex cases. shlex.split() can illustrate
how to determine the correct tokenization for args:
import shlex, subprocess
command_line = input()
args = shlex.split(command_line)
print(args)
p = subprocess.Popen(args) # Success!
shlex is included in standard library so you need not to install it.
Writing it in a single line like str.split() should look like:
import shlex
import subprocess
command = "ls -l"
proc = subprocess.Popen(shlex.split(command) , stdout = subprocess.PIPE , stderr = subprocess.PIPE)
output , errors = proc.communicate()
print(output , errors)

Python improper string quote

Hi I am embedding a shell script in python which I wanna execute as echo args Where
args = """-ne '#!/bin/sh\n\
update_bridge_config () {\n\
if [ $DATA_BRIDGE_IF ]; then\n\
echo "DATA_BRIDGE_IF is $DATA_BRIDGE_IF"\n\
sudo /usr/bin/ovs-vsctl --may-exist add-br "br-$DATA_BRIDGE_IF"\n\
fi\n\
}\n\
ETH0_MAC_ADDR=`ip link show eth0 | awk '/ether/ {print $2}'`\n\
ETH1_MAC_ADDR=`ip link show eth1 | awk '/ether/ {print $2}'`\n\
ETH2_MAC_ADDR=`ip link show eth2 | awk '/ether/ {print $2}'`\n\ ' >> myScript.sh"""
When I open the file I found those particular line is getting changed as
ETH0_MAC_ADDR= 'ip link show eth0 | awk /ether/ {print }'
Any idea what am missing ?
EDIT:: Look the ` are getting replaced by ‘ . And the ‘ are missing as well as $2

It's a single quote issue because you are starting with a single quote right after ne """-ne '#!/bin/sh ... . Because of this you are not getting $2 and facing other single quote abnormalities.
Use '"'"' to escape '
ETH0_MAC_ADDR=ip link show eth0 | awk '"'"'/ether/ {print $2}'"'"'
This should work. Mind it ! this issue is not pythonic but shell