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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_post_data(self):
        '''
        Get all the arguments from post request. Only get the first argument by default.
        '''
        post_data = {}
        for key in self.request.arguments:
            post_data[key] = self.get_arguments(key)[0]
        return post_data