capybara/virtualenv/lib/python2.7/site-packages/pip/_vendor/pkg_resources/__init__.py
def subscribe(self, callback):
        """Invoke `callback` for all distributions (including existing ones)"""
        if callback in self.callbacks:
            return
        self.callbacks.append(callback)
        for dist in self:
            callback(dist)
def subscribe(self, callback):
        """Invoke `callback` for all distributions (including existing ones)"""
        if callback in self.callbacks:
            return
        self.callbacks.append(callback)
        for dist in self:
            callback(dist)
def subscribe ( self , callback ) : if callback in self . callbacks : return self . callbacks . append ( callback ) for dist in self : callback ( dist )
Invoke `callback` for all distributions (including existing ones)
Invoke callback for all distributions ( including existing ones )