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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 _build_fields(self, defaults, fields):
 """Return provided fields including any in defaults # Verify that ``fields`` is used {'foo': 'one'} True # Verify that ``@fields`` in ``defaults`` is used {'foo': 'one', 'bar': 'two'} True # Verify that ``fields`` takes precedence {'foo': 'one'} True """

        return dict(list(defaults.get('@fields', {}).items()) + list(fields.items()))