from pathlib import Path
from decimal import Decimal
import csv,json
p=Path(__file__).parent;d=json.loads((p/'dialects.json').read_text(encoding='utf-8'));r={}
for n,k in d.items():
 with (p/n).open(encoding='utf-8',newline='') as f:r[n]=[str(Decimal(a['value'].replace(k['decimal_mark'],'.'))) for a in csv.DictReader(f,delimiter=k['delimiter'])]
assert r['decimal-comma.csv']==r['decimal-dot.csv']==['1.25','2.50'];print(json.dumps(r,indent=2))