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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 to_nullable_array(value):
 """ Converts value into array object. Single values are converted into arrays with a single element. :param value: the value to convert. :return: array object or None when value is None. """

        # Shortcuts
        if value == None:
            return None
        if type(value) == list:
            return value 

        if type(value) in [tuple, set]:
            return list(value)
            
        return [value]