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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 created(cls, data=None):
 """Shortcut API for HTTP 201 `Created` response. Args: data (object):
 Response key/value data. Returns: WSResponse Instance. """

        if cls.expose_status:  # pragma: no cover
            cls.response.content_type = 'application/json'
            cls.response._status_line = '201 Created'

        return cls(201, data=data).to_json