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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 create_video(video_data):
 """ Called on to create Video objects in the database create_video is used to create Video objects whose children are EncodedVideo objects which are linked to Profile objects. This is an alternative to the HTTP requests so it can be used internally. The VideoSerializer is used to deserialize this object. If there are duplicate profile_names, the entire creation will be rejected. If the profile is not found in the database, the video will not be created. Args: video_data (dict):
 { url: api url to the video edx_video_id: ID of the video duration: Length of video in seconds client_video_id: client ID of video encoded_video: a list of EncodedVideo dicts url: url of the video file_size: size of the video in bytes profile: ID of the profile courses: Courses associated with this video image: poster image file name for a particular course } Raises: Raises ValCannotCreateError if the video cannot be created. Returns the successfully created Video object """


    serializer = VideoSerializer(data=video_data)
    if serializer.is_valid():
        serializer.save()
        return video_data.get("edx_video_id")
    else:
        raise ValCannotCreateError(serializer.errors)