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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 from_dict(vpc_config, do_sanitize=False):
 """ Extracts subnets and security group ids as lists from a VpcConfig dict Args: vpc_config (dict):
 a VpcConfig dict containing 'Subnets' and 'SecurityGroupIds' do_sanitize (bool):
 whether to sanitize the VpcConfig dict before extracting values Returns: Tuple of lists as (subnets, security_group_ids) If vpc_config parameter is None, returns (None, None) Raises: ValueError if sanitize enabled and vpc_config is invalid KeyError if sanitize disabled and vpc_config is missing key(s) """

    if do_sanitize:
        vpc_config = sanitize(vpc_config)
    if vpc_config is None:
        return None, None
    return vpc_config[SUBNETS_KEY], vpc_config[SECURITY_GROUP_IDS_KEY]