Do not modify data_file which is used by other import methods

wizard/account_bank_statement_import.py

@@ -69,7 +69,6 @@ class AccountBankStatementImport(models.TransientModel):
                 if (test_versionB == None):
                     # for files generated after december 2017
                     file_version = "version_C"
-
             parse_line_1 = re.compile(
                 self.regexp_version[file_version]['line_1']).search(data_file[0])
             bank_group_code = parse_line_1.group('bank_group_code')
@@ -85,7 +84,7 @@ class AccountBankStatementImport(models.TransientModel):
             opening_balance = float(re.compile(self.regexp_version[file_version]['line_opening_balance']).search(data_file[len(data_file)-1]).group('balance').replace(',','.'))
 
         except Exception as e:
-            _logger.error(e)
+            _logger.debug(e)
             return False
         return (file_version, bank_group_code, openning_date, closing_date,
                 bank_account_number, opening_balance, closing_balance,
@@ -93,8 +92,8 @@ class AccountBankStatementImport(models.TransientModel):
 
     @api.model
     def _parse_file(self, data_file):
-        data_file = data_file.decode('iso-8859-1').splitlines()
-        result = self._check_file(data_file)
+        data_file_split = data_file.decode('iso-8859-1').splitlines()
+        result = self._check_file(data_file_split)
         if not result:
             return super(AccountBankStatementImport, self)._parse_file(
                 data_file)
@@ -104,7 +103,7 @@ class AccountBankStatementImport(models.TransientModel):
         total_amt = 0.00
         try:
             index = 0
-            for line in data_file[5:len(data_file)-1]:
+            for line in data_file_split[5:len(data_file_split)-1]:
                 transaction = re.compile(self.regexp_version[file_version]['line_debit']).search(line)
                 if (transaction != None):
                     transaction_amount = float(transaction.group('debit').replace(',','.'))