Add weeks to holders

Author: Mauko Quiroga

openfisca_core/holders.py

@@ -12,7 +12,7 @@
 from openfisca_core.data_storage import InMemoryStorage, OnDiskStorage
 from openfisca_core.errors import PeriodMismatchError
 from openfisca_core.indexed_enums import Enum
-from openfisca_core.periods import MONTH, YEAR, ETERNITY
+from openfisca_core.periods import WEEK, MONTH, YEAR, ETERNITY
 from openfisca_core.tools import eval_expression
 
 log = logging.getLogger(__name__)
@@ -209,6 +209,10 @@ def _set(self, period, value):
         if self.variable.definition_period != ETERNITY:
             if period is None:
                 raise ValueError('A period must be specified to set values, except for variables with ETERNITY as as period_definition.')
+
+            if self.variable.definition_period == WEEK:
+                period = periods.period(f"{WEEK}:{period}")
+
             if (self.variable.definition_period != period.unit or period.size > 1):
                 name = self.variable.name
                 period_size_adj = f'{period.unit}' if (period.size == 1) else f'{period.size}-{period.unit}s'