fix robcarver17#946

Author: rob

CONTRIBUTING.md

@@ -57,6 +57,7 @@ In general, we try and follow the original texts: [PEP 8](https://peps.python.or
 ### General
 
 - Unless there is a single parameter, passed parameters should be explicit.
+- It is almost always better to use `arg_not_supplied` (`from syscore.objects import arg_not_supplied`) as a default argument then resolve it to the appropriate value in the function. 
 - Type hints should be used, with Unions if required `from typing import Union` and Lists / Dicts ...`from typing import List, Dict`
 - Verbose doc strings specifying all the parameters are no longer required (superseded by type hints)
 

syscore/pandas/pdutils.py

@@ -754,6 +754,7 @@ def sumup_business_days_over_pd_series_without_double_counting_of_closing_data(
 
     return joint_data
 
+## FIXME HERE
 
 def replace_all_zeros_with_nan(result: pd.Series) -> pd.Series:
     check_result = copy(result)

sysdata/csv/csv_futures_contract_prices.py

@@ -17,7 +17,7 @@
 class ConfigCsvFuturesPrices:
     input_date_index_name: str = "DATETIME"
     input_date_format: str = DEFAULT_DATE_FORMAT_FOR_CSV
-    input_column_mapping: dict = None
+    input_column_mapping: dict = arg_not_supplied
     input_skiprows: int = 0
     input_skipfooter: int = 0
     apply_multiplier: float = 1.0