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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 js_link(self, attr, other, other_attr):
        ''' Link two Bokeh model properties using JavaScript.

        This is a convenience method that simplifies adding a CustomJS callback
        to update one Bokeh model property whenever another changes value.

        Args:

            attr (str) :
                The name of a Bokeh property on this model

            other (Model):
                A Bokeh model to link to self.attr

            other_attr (str) :
                The property on ``other`` to link together

        Added in version 1.1

        Raises:

            ValueError

        Examples:

            This code with ``js_link``:

            .. code :: python

                select.js_link('value', plot, 'sizing_mode')

            is equivalent to the following:

            .. code:: python

                from bokeh.models import CustomJS
                select.js_on_change('value',
                    CustomJS(args=dict(other=plot),
                             code="other.sizing_mode = this.value"
                    )
                )

        '''
        if attr not in self.properties():
            raise ValueError("%r is not a property of self (%r)" % (attr, self))

        if not isinstance(other, Model):
            raise ValueError("'other' is not a Bokeh model: %r" % other)

        if other_attr not in other.properties():
            raise ValueError("%r is not a property of other (%r)" % (other_attr, other))

        from bokeh.models.callbacks import CustomJS
        cb = CustomJS(args=dict(other=other), code="other.%s = this.%s" % (other_attr, attr))

        self.js_on_change(attr, cb)