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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 color_conversion_function(start_type, target_type):
 """ Decorator to indicate a function that performs a conversion from one color space to another. This decorator will return the original function unmodified, however it will be registered in the _conversion_manager so it can be used to perform color space transformations between color spaces that do not have direct conversion functions (e.g., Luv to CMYK). Note: For a conversion to/from RGB supply the BaseRGBColor class. :param start_type: Starting color space type :param target_type: Target color space type """

    def decorator(f):
        f.start_type = start_type
        f.target_type = target_type
        _conversion_manager.add_type_conversion(start_type, target_type, f)
        return f

    return decorator