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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 ignore_cidr(vm_, ip):
    '''
    Return True if we are to ignore the specified IP. Compatible with IPv4.
    '''
    if HAS_NETADDR is False:
        log.error('Error: netaddr is not installed')
        return 'Error: netaddr is not installed'

    cidr = config.get_cloud_config_value(
        'ignore_cidr', vm_, __opts__, default='', search_global=False
    )
    if cidr != '' and all_matching_cidrs(ip, [cidr]):
        log.warning('IP "%s" found within "%s"; ignoring it.', ip, cidr)
        return True

    return False