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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_nameserver_credentials(self, working_directory, num_tries=60, interval=1):
 		""" 		loads the nameserver credentials in cases where master and workers share a filesystem 		Parameters 			working_directory: str 				the working directory for the HPB run (see master) 			num_tries: int 				number of attempts to find the file (default 60) 			interval: float 				waiting period between the attempts 		"""

		fn = os.path.join(working_directory, 'HPB_run_%s_pyro.pkl'%self.run_id)
		
		for i in range(num_tries):
			try:
				with open(fn, 'rb') as fh:
					self.nameserver, self.nameserver_port = pickle.load(fh)
				return
			except FileNotFoundError:
				self.logger.warning('config file %s not found (trail %i/%i)'%(fn, i+1, num_tries))
				time.sleep(interval)
			except:
				raise
		raise RuntimeError("Could not find the nameserver information, aborting!")