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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 get_component(self, entity, component_type, missing=MISSING):
 """Get the component of type component_type associated with entity. Long-hand for :func:`essence.Entity.get`. :param entity: entity to query :type entity: :class:`essence.Entity` :param component_type: component to add to the entity :type component_type: The :class:`type` of a :class:`Component` subclass :param missing: value to return if :type missing: :class:`essence.Component` :raises:"""

        relation = self._get_relation(component_type)
        if entity not in relation:
            if missing is MISSING:
                raise NoSuchComponentError()
            else:
                return missing
        return relation[entity]