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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_classpath_tuples(self, classpath, target):
 """Validates that all files are located within the working directory, to simplify relativization. :param classpath: The list of classpath tuples. Each tuple is a 2-tuple of ivy_conf and ClasspathEntry. :param target: The target that the classpath tuple is being registered for. :raises: `TaskError` when the path is outside the work directory """

    for classpath_tuple in classpath:
      conf, classpath_entry = classpath_tuple
      path = classpath_entry.path
      if os.path.relpath(path, self._pants_workdir).startswith(os.pardir):
        raise TaskError(
          'Classpath entry {} for target {} is located outside the working directory "{}".'
          .format(path, target.address.spec, self._pants_workdir))