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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 content_val(self, ymldata=None, messages=None):
 """Validates the Command Dictionary to ensure the contents for each of the fields meets specific criteria regarding the expected types, byte ranges, etc."""


        self._ymlproc = YAMLProcessor(self._ymlfile, False)

        # Turn off the YAML Processor
        log.debug("BEGIN: Content-based validation of Command dictionary")
        if ymldata is not None:
            cmddict = ymldata
        elif ymldata is None and self._ymlproc.loaded:
            cmddict = self._ymlproc.data
        elif not self._ymlproc.loaded:
            raise util.YAMLError("YAML failed to load.")

        try:
            # instantiate the document number. this will increment in order to
            # track the line numbers and section where validation fails
            docnum = 0

            # boolean to hold argument validity
            argsvalid = True

            # list of rules to validate against
            rules = []

            ### set the command rules
            #
            # set uniqueness rule for command names
            rules.append(UniquenessRule('name', "Duplicate command name: %s", messages))

            # set uniqueness rule for opcodes
            rules.append(UniquenessRule('opcode', "Duplicate opcode: %s", messages))
            #
            ###
            for cmdcnt, cmddefn in enumerate(cmddict[0]):
                # check the command rules
                for rule in rules:
                    rule.check(cmddefn)

                # list of argument rules to validate against
                argrules = []

                ### set rules for command arguments
                #
                # set uniqueness rule for opcodes
                argrules.append(UniquenessRule('name', "Duplicate argument name: " + cmddefn.name + ".%s", messages))

                # set type rule for arg.type
                argrules.append(TypeRule('type', "Invalid argument type for argument: " + cmddefn.name + ".%s", messages))

                # set argument size rule for arg.type.nbytes
                argrules.append(TypeSizeRule('nbytes', "Invalid argument size for argument: " + cmddefn.name + ".%s", messages))

                # set argument enumerations rule to check no enumerations contain un-quoted YAML special variables
                argrules.append(EnumRule('enum', "Invalid enum value for argument: " + cmddefn.name + ".%s", messages))

                # set byte order rule to ensure proper ordering of aruguments
                argrules.append(ByteOrderRule('bytes', "Invalid byte order for argument: " + cmddefn.name + ".%s", messages))
                #
                ###

                argdefns = cmddefn.argdefns
                for arg in argdefns:
                    # check argument rules
                    for rule in argrules:
                        rule.check(arg)

                # check if argument rule failed, if so set the validity to False
                if not all(r.valid is True for r in argrules):
                    argsvalid = False

            log.debug("END: Content-based validation complete for '%s'", self._ymlfile)

            # check validity of all command rules and argument validity
            return all(rule.valid is True for rule in rules) and argsvalid

        except util.YAMLValidationError, e:
            # Display the error message
            if messages is not None:
                if len(e.message) < 128:
                    msg = "Validation Failed for YAML file '" + self._ymlfile + "': '" + str(e.message) + "'"
                else:
                    msg = "Validation Failed for YAML file '" + self._ymlfile + "'"

                log.error(msg)
                self.ehandler.process(docnum, self.ehandler.doclines, e, messages)
                return False