def update_apns_channel(APNSChannelRequest=None, ApplicationId=None):
    """
    Use to update the APNs channel for an app.
    
    
    :example: response = client.update_apns_channel(
        APNSChannelRequest={
            'Certificate': 'string',
            'PrivateKey': 'string'
        },
        ApplicationId='string'
    )
    
    
    :type APNSChannelRequest: dict
    :param APNSChannelRequest: [REQUIRED] Apple Push Notification Service channel definition.
            Certificate (string) -- The distribution certificate from Apple.
            PrivateKey (string) -- The certificate private key.
            

    :type ApplicationId: string
    :param ApplicationId: [REQUIRED]

    :rtype: dict
    :return: {
        'APNSChannelResponse': {
            'ApplicationId': 'string',
            'CreationDate': 'string',
            'Id': 'string',
            'IsArchived': True|False,
            'LastModifiedBy': 'string',
            'LastModifiedDate': 'string',
            'Platform': 'string',
            'Version': 123
        }
    }
    
    
    :returns: 
    (dict) -- 200 response
    APNSChannelResponse (dict) -- Apple Distribution Push Notification Service channel definition.
    ApplicationId (string) -- The ID of the application to which the channel applies.
    CreationDate (string) -- When was this segment created
    Id (string) -- The unique channel ID.
    IsArchived (boolean) -- Is this channel archived
    LastModifiedBy (string) -- Who last updated this entry
    LastModifiedDate (string) -- Last date this was updated
    Platform (string) -- The platform type. Will be APNS.
    Version (integer) -- Version of channel
    
    
    
    
    
    """
    pass
