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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 _process_arguments(self, arguments):
 """Process the arguments :param arguments: arguments string of a message :type arguments: :class:`str` | None :returns: A list of arguments :rtype: :class:`list` of :class:`str` | None :raises: None """

        if not arguments:
            return None
        a = arguments.split(" :", 1)
        arglist = a[0].split()
        if len(a) == 2:
            arglist.append(a[1])
        return arglist