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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 migrate_paths(opts):
    '''
    Migrate old minion and master pki file paths to new ones.
    '''
    oldpki_dir = os.path.join(syspaths.CONFIG_DIR, 'pki')

    if not os.path.exists(oldpki_dir):
        # There's not even a pki directory, don't bother migrating
        return

    newpki_dir = opts['pki_dir']

    if opts['default_include'].startswith('master'):
        keepers = ['master.pem',
                   'master.pub',
                   'syndic_master.pub',
                   'minions',
                   'minions_pre',
                   'minions_rejected',
                   ]
        if not os.path.exists(newpki_dir):
            os.makedirs(newpki_dir)
        for item in keepers:
            oi_path = os.path.join(oldpki_dir, item)
            ni_path = os.path.join(newpki_dir, item)
            if os.path.exists(oi_path) and not os.path.exists(ni_path):
                shutil.move(oi_path, ni_path)

    if opts['default_include'].startswith('minion'):
        keepers = ['minion_master.pub',
                   'minion.pem',
                   'minion.pub',
                   ]
        if not os.path.exists(newpki_dir):
            os.makedirs(newpki_dir)
        for item in keepers:
            oi_path = os.path.join(oldpki_dir, item)
            ni_path = os.path.join(newpki_dir, item)
            if os.path.exists(oi_path) and not os.path.exists(ni_path):
                shutil.move(oi_path, ni_path)