Simple python function to check if host is up using ping, allows setting of waittime

HostUp.py

def HostUp(hostname, waittime=1000):
    '''Function returns True if host IP returns a ping, else False'''
    assert isinstance(hostname, str), \
        "IP/hostname must be provided as a string."
    if os.system("ping -c 1 -W " + str(waittime) + " " +
                 hostname + " > /dev/null 2>&1") is 0:
        HOST_UP = True
    else:
        HOST_UP = False
    return HOST_UP