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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 decode(cls, command_str):
 """Decode a string encoded command back into a Command object. Args: command_str (str):
 The encoded command string output from a previous call to encode. Returns: Command: The decoded Command object. """


        name, _, arg = command_str.partition(" ")

        args = []

        if len(arg) > 0:
            if arg[0] != '{' or arg[-1] != '}':
                raise DataError("Invalid command, argument is not contained in { and }", arg=arg, cmd=name)

            arg = arg[1:-1]
            args = arg.split(",")

        proc = []

        for arg in args:
            if arg.startswith("hex:"):
                arg = unhexlify(arg[4:]).decode('utf-8')

            proc.append(arg)

        return Command(name, proc)