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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 _parse_normalizations(self, normalizations):
 """Returns a list of parsed normalizations. Iterates over a list of normalizations, removing those not correctly defined. It also transform complex items to have a common format (list of tuples and strings). Args: normalizations: List of normalizations to parse. Returns: A list of normalizations after being parsed and curated. """

        parsed_normalizations = []

        if isinstance(normalizations, list):
            for item in normalizations:
                normalization = self._parse_normalization(item)
                if normalization:
                    parsed_normalizations.append(normalization)
        else:
            raise ConfigError('List expected. Found %s' % type(normalizations))

        return parsed_normalizations