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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_region(cls, resource=None):
 """Retrieve region from standard environmental variables or file name. More information of the following link: http://goo.gl/Vb9Jky """

        if resource:
            resource_info = cls.parse_remote(resource)
            if resource_info.region:
                return resource_info.region

        return os.environ.get("AWS_DEFAULT_REGION", cls._DEFAULT_REGION)