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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 add(self, text="", default_continuousAdd=True):
 		"""add some turtle text"""

		if not text and default_continuousAdd:
			self.continuousAdd()
		else:
			pprefix = ""
			for x,y in self.rdflib_graph.namespaces():
				pprefix += "@prefix %s: <%s> . \n" % (x, y)
			# add final . if missing
			if text and (not text.strip().endswith(".")):
				text += " ."
			# smart replacements
			text = text.replace(" sub ", " rdfs:subClassOf ")
			text = text.replace(" class ", " owl:Class ")
			# finally
			self.rdflib_graph.parse(data=pprefix+text, format="turtle")