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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 MSBuild(self):
 """ Microsoft Build Engine """

        if self.vc_ver < 12.0:
            return []
        elif self.vc_ver < 15.0:
            base_path = self.si.ProgramFilesx86
            arch_subdir = self.pi.current_dir(hidex86=True)
        else:
            base_path = self.si.VSInstallDir
            arch_subdir = ''

        path = r'MSBuild\%0.1f\bin%s' % (self.vc_ver, arch_subdir)
        build = [os.path.join(base_path, path)]

        if self.vc_ver >= 15.0:
            # Add Roslyn C# & Visual Basic Compiler
            build += [os.path.join(base_path, path, 'Roslyn')]

        return build