Model.clean() [source] This method should be used to provide custom model validation, and

class TruncYear(expression, output_field=None, tzinfo=None, **extra) [source]

class ExtractSecond(expression, tzinfo=None, **extra) [source] lookup_name

annotate(*args, **kwargs) Annotates each object in the QuerySet with the provided list of query

lhs The left-hand side - what is being looked up. The object must follow the Query Expression API

DecimalField.max_digits The maximum number of digits allowed in the number. Note that this number must be greater than or equal

Field.validators A list of validators to run for this field. See the validators documentation for more

sample By default, StdDev returns the population standard deviation. However, if sample=True, the

Field.one_to_one Boolean flag that is True if the field has a one-to-one relation, such as a OneToOneField;

exists() Returns True if the QuerySet contains any results, and False if not. This tries