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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 project_drawn(cb, msg):
 """ Projects a drawn element to the declared coordinate system """

    stream = cb.streams[0]
    old_data = stream.data
    stream.update(data=msg['data'])
    element = stream.element
    stream.update(data=old_data)
    proj = cb.plot.projection
    if not isinstance(element, _Element) or element.crs == proj:
        return None
    crs = element.crs
    element.crs = proj
    return project(element, projection=crs)