def METHOD_NAME(self, psnPattern=''):
    if not isinstance(psnPattern, (str, bytes)):
        raise TypeError('psnPattern argument must be of type str or bytes')
    callname = 'data-processing'
    results = self.genericLookup(callname)
    mapping = {}
    psnPattern = re.compile(psnPattern)
    for entry in results:
        if psnPattern.match(entry['psn_name']):
            mapping.setdefault(entry['psn_name'], set()).add(entry['phedex_name'])
    return mapping