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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 _validate_and_parse_course_key(self, course_key):
 """ Returns a validated parsed CourseKey deserialized from the given course_key. """

        try:
            return CourseKey.from_string(course_key)
        except InvalidKeyError:
            raise ValidationError(_("Invalid course key: {}").format(course_key))