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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 build(self):
 """Run the build command specified in index.yaml."""

        for cmd in self.build_cmds:
            log.info('building command: {}'.format(cmd))
            full_cmd = 'cd {}; {}'.format(self.analyses_path, cmd)
            log.debug('full command: {}'.format(full_cmd))
            subprocess.call(full_cmd, shell=True)
            log.info('build done')