Usage
GetFileUpload(assignment, questionIdentifier, download = FALSE, file.ext = NULL, 
				open.file.in.browser = FALSE, keypair = credentials(), print = TRUE, 
				browser = FALSE, log.requests = TRUE, sandbox = FALSE)
Arguments
assignment
A character string containing an AssignmentId, or a vector of character strings each containing an AssignmentId.
questionIdentifier
A question identifer for a file upload question, as specified in the question parameter of CreateHIT or in the placeholder of a HIT template created in the RUI.
download
A logical specifying whether the file(s) should be downloaded and saved in the working directory. Default is FALSE.
file.ext
An optional character string specifying the file extension of the uploaded files (used only if download=TRUE).
open.file.in.browser
A logical specifying whether the file should be opened in the user's default web browser.
keypair
A two-item character vector containing an AWS Access Key ID in the first position and the corresponding Secret Access Key in the second position. Set default with credentials. print
Optionally print the results of the API request to the standard output. Default is TRUE.
browser
Optionally open the request in the default web browser, rather than opening in R. Default is FALSE.
log.requests
A logical specifying whether API requests should be logged. Default is TRUE. See readlogfile for details. sandbox
Optionally execute the request in the MTurk sandbox rather than the live server.  Default is FALSE.