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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 preloop(self):
 """if the parser is not already set, loads the parser."""

        if not self.parser:
            self.stdout.write("Welcome to imagemounter {version}".format(version=__version__))
            self.stdout.write("\n")

            self.parser = ImageParser()
            for p in self.args.paths:
                self.onecmd('disk "{}"'.format(p))