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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_mine(fun):
    '''
    Return the mine function from all the targeted minions.
    Just a small helper to avoid redundant pieces of code.
    '''
    if fun in _CACHE and _CACHE[fun]:
        return _CACHE[fun]
    net_runner_opts = _get_net_runner_opts()
    _CACHE[fun] = __salt__['mine.get'](net_runner_opts.get('target'),
                                       fun,
                                       tgt_type=net_runner_opts.get('expr_form'))
    return _CACHE[fun]