{% macro construct_template(construct_function, property, source, initial_value=None) %}
{% if property.required and not property.nullable %}
{{ property.python_name }} = {{ construct_function(property, source) }}
{% else %}{# Must be nullable OR non-required #}
_{{ property.python_name }} = {{ source }}
{{ property.python_name }}: {{ property.get_type_string() }}
    {% if property.nullable %}
if _{{ property.python_name }} is None:
    {{ property.python_name }} = {% if initial_value != None %}{{ initial_value }}{% else %}None{% endif %}

    {% endif %}
    {% if not property.required %}
{% if property.nullable %}elif{% else %}if{% endif %} isinstance(_{{ property.python_name }},  Unset):
    {{ property.python_name }} = {% if initial_value != None %}{{ initial_value }}{% else %}UNSET{% endif %}

    {% endif %}
else:
    {{ property.python_name }} = {{ construct_function(property, "_" + property.python_name) }}
{% endif %}
{% endmacro %}