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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(self, result, spec):
 # noqa Yes, it's too complex. """Validate that the result has the correct structure."""

        if spec is None:
            # None matches anything.
            return
        if isinstance(spec, dict):
            if not isinstance(result, dict):
                raise ValueError('Dictionary expected, but %r found.' % result)
            if spec:
                spec_value = next(iter(spec.values()))  # Yay Python 3!
                for value in result.values():
                    self.validate(value, spec_value)
                spec_key = next(iter(spec.keys()))
                for key in result:
                    self.validate(key, spec_key)
        if isinstance(spec, list):
            if not isinstance(result, list):
                raise ValueError('List expected, but %r found.' % result)
            if spec:
                for value in result:
                    self.validate(value, spec[0])
        if isinstance(spec, tuple):
            if not isinstance(result, tuple):
                raise ValueError('Tuple expected, but %r found.' % result)
            if len(result) != len(spec):
                raise ValueError('Expected %d elements in tuple %r.' %
                                 (len(spec), result))
            for s, value in zip(spec, result):
                self.validate(value, s)
        if isinstance(spec, six.string_types):
            if not isinstance(result, six.string_types):
                raise ValueError('String expected, but %r found.' % result)
        if isinstance(spec, int):
            if not isinstance(result, int):
                raise ValueError('Integer expected, but %r found.' % result)
        if isinstance(spec, bool):
            if not isinstance(result, bool):
                raise ValueError('Boolean expected, but %r found.' % result)