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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 _get_mapping(self, section):
        '''mapping will take the section name from a Singularity recipe 
           and return a map function to add it to the appropriate place. 
           Any lines that don't cleanly map are assumed to be comments.

           Parameters
           ==========
           section: the name of the Singularity recipe section
    
           Returns
           =======
           function: to map a line to its command group (e.g., install)

        '''

        # Ensure section is lowercase
        section = section.lower()

        mapping = {"environment": self._env,
                   "comments": self._comments,
                   "runscript": self._run,
                   "labels": self._labels,
                   "setup": self._setup,
                   "files": self._files,
                   "from": self._from,
                   "post": self._post,
                   "test": self._test,
                   "help": self._comments}

        if section in mapping:
            return mapping[section]
        return self._comments