Normalizes the object into an array of scalars|arrays.
It is important to understand that the normalize() call should normalize recursively all child objects of the implementor.
NormalizerInterface $normalizer The normalizer is given so that you: can use it to normalize objects contained within this object.
string|null $format The format is optionally given to be able to normalize differently: based on different output formats.
array|scalar
public function normalize(NormalizerInterface $normalizer, $format = null);