title: flask-sqlalchemy reverse model relation query from child to parent
body: <p>I have these One To One model define and I'm trying to call the <code>parent.method1</code> inside the <code>child.call_parent_method</code></p>
  
  <pre><code>class Parent(db.Model):
      __tablename__ = 'parent'
  
      id = db.Column(db.Integer, primary_key=True)
      child = db.relationship('Child', backref='parent')
      child_id = db.Column(db.Integer, db.ForeignKey('child.id'),
                                   nullable=True)
  
      @hybrid_property
      def prop1(self)
          print 'This is method 1'
  
  
  class Child(db.Model):
       __tablename__ = 'child'
  
      id = db.Column(db.Integer, primary_key=True)
  
      def call_parent_method(self):
          self.parent.prop1
  </code></pre>
  
  <p>But what i get is:</p>
  
  <pre><code>AttributeError: 'InstrumentedList' object has no attribute 'prop1'
  </code></pre>