Impacted versions:
Master branch, should by 12.0

Steps to reproduce:
Install a third party addon with localization po file in i18n folder, even loading translation manually, the translation won't work, The console reports error: Translation .... not found in reference pot, skipping.
Reverse the change of  "odoo/tools/translate.py" in this commit, the issue was gone.

Expected behavior:
The po translation works as before.



'es_AR': 'Spanish_Spain',
    'es_BO': 'Spanish_Spain',
    'es_CL': 'Spanish_Spain',
    'es_CO': 'Spanish_Spain',
    'es_CR': 'Spanish_Spain',
    'es_DO': 'Spanish_Spain',
    'es_EC': 'Spanish_Spain',
    'es_ES': 'Spanish_Spain',
    'es_GT': 'Spanish_Spain',
    'es_HN': 'Spanish_Spain',
    'es_MX': 'Spanish_Spain',
    'es_NI': 'Spanish_Spain',
    'es_PA': 'Spanish_Spain',
    'es_PE': 'Spanish_Spain',
    'es_PR': 'Spanish_Spain',
    'es_PY': 'Spanish_Spain',
    'es_SV': 'Spanish_Spain',
    'es_UY': 'Spanish_Spain',
    'es_VE': 'Spanish_Spain',
    'sv_SE': 'Swedish_Sweden',
    'ta_IN': 'English_Australia',
    'th_TH': 'Thai_Thailand',
    'tr_TR': 'Turkish_Turkey',
    'uk_UA': 'Ukrainian_Ukraine',
    'vi_VN': 'Vietnamese_Viet Nam',
    'tlh_TLH': 'Klingon',
}
ENGLISH_SMALL_WORDS = set("as at by do go if in me no of ok on or to up us we".split())
import csv 
class UNIX_LINE_TERMINATOR(csv.excel):