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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _validate_collections_have_default_values(class_name, property_name, property_descriptor):
 """Validate that if the property is of collection type, it has a specified default value."""

    # We don't want properties of collection type having "null" values, since that may cause
    # unexpected errors during GraphQL query execution and other operations.
    if property_descriptor.type_id in COLLECTION_PROPERTY_TYPES:
        if property_descriptor.default is None:
            raise IllegalSchemaStateError(u'Class "{}" has a property "{}" of collection type with '
                                          u'no default value.'.format(class_name, property_name))