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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 update(self,updates={}):
 		""" 			update csp_default.json with dict 			 			if file empty add default-src and create dict 		"""

		try:
			csp = self.read()
		except:
			csp = {'default-src':"'self'"}
			self.write(csp)
		csp.update(updates)
		self.write(csp)