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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 bind(self, interface, to=None, scope=None):
 """Bind an interface to an implementation. :param interface: Interface or :func:`Key` to bind. :param to: Instance or class to bind to, or an explicit :class:`Provider` subclass. :param scope: Optional :class:`Scope` in which to bind. """

        if type(interface) is type and issubclass(interface, (BaseMappingKey, BaseSequenceKey)):
            return self.multibind(interface, to, scope=scope)
        key = BindingKey.create(interface)
        self._bindings[key] = self.create_binding(interface, to, scope)