from subprocess import call
import subprocess

subprocess.call(['sudo', 'hciconfig', 'hci0', 'piscan'])

really works fine. Thanks much

wpa_cli reconfigure. I get the error, Failed to connect to non-global ctrl_ifname: (null) error: No such file or directory so need help. How can I resolve this?
We found that Bluetooth chip in RPi is gone .Please suggest a way to rectify this problem.