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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_users(self, usernames):
 """Fetch user info for given usernames :param username: The usernames you want metadata for (max. 50) """


        if self.standard_grant_type is not "authorization_code":
            raise DeviantartError("Authentication through Authorization Code (Grant Type) is required in order to connect to this endpoint.")

        response = self._req('/user/whois', post_data={
            "usernames":usernames
        })

        users = []

        for item in response['results']:
            u = User()
            u.from_dict(item)
            users.append(u)

        return users