get pcdm:hasFile for this resource

		Args:
			retrieve (bool): if True, issue .refresh() on resource thereby confirming existence and retrieving payload

def get_files(self, retrieve=False):

		'''
		get pcdm:hasFile for this resource

		Args:
			retrieve (bool): if True, issue .refresh() on resource thereby confirming existence and retrieving payload
		'''

		if self.exists and hasattr(self.rdf.triples, 'pcdm') and hasattr(self.rdf.triples.pcdm, 'hasFile'):
			files = [ self.repo.parse_uri(uri) for uri in self.rdf.triples.pcdm.hasFile ]

			# return
			return files

		else:
			return []