title: Can I use data loader without batching
body: <p>What I am really interested in with data-loader is the per request caching. For example say my graphql query needs to call getUser("id1") 3x. I would like something to dedupe that call. </p>
  
  <p>However it seems like with data-loader I need to pass in an array of keys into my batch function, and multiple requests will be batched into one api calls. </p>
  
  <p>This has me making a few assumptions that i dont like: </p>
  
  <p>1.) That each service I am calling has a batch api (some of the ones im dealing with do not). </p>
  
  <p>2.) What if multiple calls get batched into 1 api call, and that call fails because 1 of the items was not found. Normally I could handle this by returning null for that field, and that could be a valid case. Now however my entire call may fail, if the batch API decides to throw an error since 1 item was not found. </p>
  
  <p>Is there anyway to use dataloader with single-key requests. </p>