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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 is_connection_to_a_vcenter(service_instance):
    '''
    Function that returns True if the connection is made to a vCenter Server and
    False if the connection is made to an ESXi host

    service_instance
        The Service Instance from which to obtain managed object references.
    '''
    try:
        api_type = service_instance.content.about.apiType
    except vim.fault.NoPermission as exc:
        log.exception(exc)
        raise salt.exceptions.VMwareApiError(
            'Not enough permissions. Required privilege: '
            '{}'.format(exc.privilegeId))
    except vim.fault.VimFault as exc:
        log.exception(exc)
        raise salt.exceptions.VMwareApiError(exc.msg)
    except vmodl.RuntimeFault as exc:
        log.exception(exc)
        raise salt.exceptions.VMwareRuntimeError(exc.msg)
    log.trace('api_type = %s', api_type)
    if api_type == 'VirtualCenter':
        return True
    elif api_type == 'HostAgent':
        return False
    else:
        raise salt.exceptions.VMwareApiError(
            'Unexpected api type \'{0}\' . Supported types: '
            '\'VirtualCenter/HostAgent\''.format(api_type))