<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _create_virtual_network(self, region, resource_group_name, vnet_name):
 """ Create a vnet in the given resource group with default address space. """

        vnet_config = {
            'location': region,
            'address_space': {
                'address_prefixes': ['10.0.0.0/27']
            }
        }

        try:
            vnet_setup = self.network.virtual_networks.create_or_update(
                resource_group_name, vnet_name, vnet_config
            )
        except Exception as error:
            raise AzureCloudException(
                'Unable to create vnet: {0}.'.format(error)
            )

        vnet_setup.wait()