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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 unrecord(plugin_or_specs, filename):
    '''
    Remove a database migration record.

    \b
    A record can be expressed with the following syntaxes:
     - plugin filename
     - plugin fliename.js
     - plugin:filename
     - plugin:fliename.js
    '''
    plugin, filename = normalize_migration(plugin_or_specs, filename)
    migration = get_migration(plugin, filename)
    if migration:
        log.info('Removing migration %s:%s', plugin, filename)
        db = get_db()
        db.eval(UNRECORD_WRAPPER, migration['_id'])
    else:
        log.error('Migration not found %s:%s', plugin, filename)