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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 get_requires(self, requires_types):
 """Extracts requires of given types from metadata file, filter windows specific requires. """

        if not isinstance(requires_types, list):
            requires_types = list(requires_types)
        extracted_requires = []
        for requires_name in requires_types:
            for requires in self.json_metadata.get(requires_name, []):
                if 'win' in requires.get('environment', {}):
                    continue
                extracted_requires.extend(requires['requires'])
        return extracted_requires