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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 native(self, value, context=None):
 		"""Convert the given string into a list of substrings."""

		
		separator = self.separator.strip() if self.strip and hasattr(self.separator, 'strip') else self.separator
		value = super().native(value, context)
		
		if value is None:
			return self.cast()
		
		if hasattr(value, 'split'):
			value = value.split(separator)
		
		value = self._clean(value)
		
		try:
			return self.cast(value) if self.cast else value
		except Exception as e:
			raise Concern("{0} caught, failed to perform array transform: {1}", e.__class__.__name__, str(e))