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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 has_option(self, option_name):
 		""" 		Check that an option exists. 		:param str option_name: The name of the option to check. 		:return: True of the option exists in the configuration. 		:rtype: bool 		"""

		if self.prefix:
			option_name = self.prefix + self.seperator + option_name
		item_names = option_name.split(self.seperator)
		node = self._storage
		for item_name in item_names:
			if node is None:
				return False
			if not item_name in node:
				return False
			node = node[item_name]
		return True