Remove unused validator
This was basically used to check if something was inside a dictionary,
but we ended up using another method for this.
@@ -72,15 +72,6 @@ def validate_choice(value, choices):
return value
-def validate_value_exists(value, container):
- """Check that ``value`` exists in ``container``."""
- if value not in container:
- raise ValidationError(value, VALUE_NOT_FOUND)
- if isinstance(container, dict):
- return container[value]
- return value
-
-
def validate_bool(value):
"""Check that ``value`` is an boolean value."""
if value not in (0, 1, False, True):
