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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 init_git_pillar(opts):
    '''
    Clear out the ext pillar caches, used when the master starts
    '''
    ret = []
    for opts_dict in [x for x in opts.get('ext_pillar', [])]:
        if 'git' in opts_dict:
            try:
                pillar = salt.utils.gitfs.GitPillar(
                    opts,
                    opts_dict['git'],
                    per_remote_overrides=git_pillar.PER_REMOTE_OVERRIDES,
                    per_remote_only=git_pillar.PER_REMOTE_ONLY,
                    global_only=git_pillar.GLOBAL_ONLY)
                ret.append(pillar)
            except salt.exceptions.FileserverConfigError:
                if opts.get('git_pillar_verify_config', True):
                    raise
                else:
                    log.critical('Could not initialize git_pillar')
    return ret