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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def execute_ping(host_list, remote_user, remote_pass,
                 sudo=False, sudo_user=None, sudo_pass=None):
    '''
    Execute ls on some hosts
    '''
    runner = spam.ansirunner.AnsibleRunner()
    result, failed_hosts = runner.ansible_perform_operation(
        host_list=host_list,
        remote_user=remote_user,
        remote_pass=remote_pass,
        sudo=sudo,
        sudo_pass=sudo_pass,
        sudo_user=sudo_user,
        module="ping")

    print result, failed_hosts
    dark_hosts = runner.ansible_get_dark_hosts(result)
    print "dark hosts: ", dark_hosts