Refactor ledger processing to explicit mapping which will make automated classfication easy

src/write.py

@@ -0,0 +1,17 @@
+from pathlib import Path
+from typing import List
+from src.models import Transaction
+
+
+LEDGER_TRANSACTION_TEMPLATE = """
+{t.date} {t.description} ; {t.row}
+    {t.account2}  {t.currency} {t.debit}
+    {t.account1}  {t.currency} {t.credit}
+"""
+
+
+def render_to_file(transactions: List[Transaction], ledger_file: Path):
+    content = "".join([LEDGER_TRANSACTION_TEMPLATE.format(t=t)
+                       for t in transactions])
+    with open(ledger_file, 'a') as f:
+        f.write(content)