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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_key(cls, container, key):
 """Create from key object."""

        if key is None:
            raise errors.NoObjectException

        # Get Key   (1123): Tue, 13 Apr 2010 14:02:48 GMT
        # List Keys (8601): 2010-04-13T14:02:48.000Z
        return cls(container,
                   name=key.name,
                   size=key.size,
                   content_type=key.content_type,
                   content_encoding=key.content_encoding,
                   last_modified=dt_from_header(key.last_modified),
                   obj_type=cls.type_cls.FILE)