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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 from_shortcode(cls, context: InstaloaderContext, shortcode: str):
 """Create a post object from a given shortcode"""

        # pylint:disable=protected-access
        post = cls(context, {'shortcode': shortcode})
        post._node = post._full_metadata
        return post