A class and generator function for proxies in R for Python functions.
An object from this class is an R function that is a proxy for a function in Python. Calls to the R function evaluate a call to the Python function. The arguments in the call are converted to equivalent Python objects; these typically include proxy objects for results previously computed through the XRPython interface.
the name of the server language function
the name of the module, if that needs to be imported
the class for the evaluator, by default and usually,
the docstring from Python, if any.
the Python argument names (not currently used).