diff --git a/guide/src/class.md b/guide/src/class.md
index 04467e8f..30d8732f 100644
--- a/guide/src/class.md
+++ b/guide/src/class.md
@@ -35,6 +35,7 @@ You can get an instance of `PyRef` by `PyRef::new`, which does 3 things:
 You can use `PyRef` just like `&T`, because it implements `Deref<Target=T>`.
 ```rust
 # use pyo3::prelude::*;
+# use pyo3::types::PyDict;
 #[pyclass]
 struct MyClass {
    num: i32,
@@ -76,7 +77,8 @@ struct MyClass {
 }
 fn return_myclass() -> Py<MyClass> {
     let gil = Python::acquire_gil();
-    Py::new(|| MyClass { num: 1 })
+    let py = gil.python();
+    Py::new(py, MyClass { num: 1 }).unwrap()
 }
 let gil = Python::acquire_gil();
 let obj = return_myclass();
@@ -144,8 +146,8 @@ Rules for the `new` method:
 
 By default `PyObject` is used as default base class. To override default base class
 `base` parameter for `class` needs to be used. Value is full path to base class.
-`__new__` method accepts `PyRawObject` object. `obj` instance must be initialized
-with value of custom class struct. Subclass must call parent's `__new__` method.
+`new` method accepts `PyRawObject` object. `obj` instance must be initialized
+with value of custom class struct. Subclass must call parent's `new` method.
 
 ```rust
 # use pyo3::prelude::*;
@@ -345,6 +347,7 @@ with`#[classmethod]` attribute.
 
 ```rust
 # use pyo3::prelude::*;
+# use pyo3::types::PyType;
 # #[pyclass]
 # struct MyClass {
 #    num: i32,
@@ -543,6 +546,8 @@ as every cycle must contain at least one mutable reference.
 Example:
 ```rust
 use pyo3::prelude::*;
+use pyo3::PyTraverseError;
+use pyo3::gc::{PyGCProtocol, PyVisit};
 
 #[pyclass]
 struct ClassWithGCSupport {
@@ -561,7 +566,9 @@ impl PyGCProtocol for ClassWithGCSupport {
     fn __clear__(&mut self) {
         if let Some(obj) = self.obj.take() {
           // Release reference, this decrements ref counter.
-          self.py().release(obj);
+          let gil = GILGuard::acquire();
+          let py = gil.python();
+          py.release(obj);
         }
     }
 }
@@ -596,11 +603,11 @@ struct MyIterator {
 
 #[pyproto]
 impl PyIterProtocol for MyIterator {
-    fn __iter__(&mut self) -> PyResult<PyObject> {
-        Ok(self.into())
+    fn __iter__(slf: PyRefMut<Self>) -> PyResult<Py<MyIterator>> {
+        Ok(slf.into())
     }
-    fn __next__(&mut self) -> PyResult<Option<PyObject>> {
-        Ok(self.iter.next())
+    fn __next__(mut slf: PyRefMut<Self>) -> PyResult<Option<PyObject>> {
+        Ok(slf.iter.next())
     }
 }
 ```
diff --git a/guide/src/exception.md b/guide/src/exception.md
index b262e457..a6c4bb3c 100644
--- a/guide/src/exception.md
+++ b/guide/src/exception.md
@@ -5,7 +5,7 @@
 You can use the `create_exception!` macro to define a new exception type:
 
 ```rust
-use pyo3::import_exception;
+use pyo3::create_exception;
 
 create_exception!(module, MyError, pyo3::exceptions::Exception);
 ```
@@ -40,7 +40,8 @@ fn main() {
 To raise an exception, first you need to obtain an exception type and construct a new [`PyErr`](https://docs.rs/pyo3/0.2.7/struct.PyErr.html), then call [`PyErr::restore()`](https://docs.rs/pyo3/0.2.7/struct.PyErr.html#method.restore) method to write the exception back to the Python interpreter's global state.
 
 ```rust
-use pyo3::{Python, PyErr, exc};
+use pyo3::{Python, PyErr};
+use pyo3::exceptions;
 
 fn main() {
     let gil = Python::acquire_gil();
@@ -63,6 +64,7 @@ has corresponding rust type, exceptions defined by `create_exception!` and `impo
 have rust type as well.
 
 ```rust
+# use pyo3::exceptions;
 # use pyo3::prelude::*;
 # fn check_for_error() -> bool {false}
 fn my_func(arg: PyObject) -> PyResult<()> {
@@ -80,7 +82,8 @@ Python has an [`isinstance`](https://docs.python.org/3/library/functions.html#is
 in `PyO3` there is a [`Python::is_instance()`](https://docs.rs/pyo3/0.2.7/struct.Python.html#method.is_instance) method which does the same thing.
 
 ```rust
-use pyo3::{Python, PyBool, PyList};
+use pyo3::Python;
+use pyo3::types::{PyBool, PyList};
 
 fn main() {
     let gil = Python::acquire_gil();
@@ -97,6 +100,7 @@ fn main() {
 To check the type of an exception, you can simply do:
 
 ```rust
+# use pyo3::exceptions;
 # use pyo3::prelude::*;
 # fn main() {
 # let gil = Python::acquire_gil();
@@ -176,7 +180,7 @@ fn tell(file: PyObject) -> PyResult<u64> {
     let py = gil.python();
 
     match file.call_method0(py, "tell") {
-        Err(_) => Err(UnsupportedOperation::new("not supported: tell")),
+        Err(_) => Err(UnsupportedOperation::py_err("not supported: tell")),
         Ok(x) => x.extract::<u64>(py),
     }    
 }
diff --git a/guide/src/function.md b/guide/src/function.md
index ccf7d3c0..65f06354 100644
--- a/guide/src/function.md
+++ b/guide/src/function.md
@@ -60,6 +60,8 @@ built-ins are new in Python 3 — in Python 2, it is simply considered to be par
 of the doc-string.
 
 ```rust
+use pyo3::prelude::*;
+
 /// add(a, b, /)
 /// --
 ///
diff --git a/guide/src/module.md b/guide/src/module.md
index 5e51b033..7a4a2ea8 100644
--- a/guide/src/module.md
+++ b/guide/src/module.md
@@ -52,27 +52,36 @@ Which means that the above Python code will print `This module is implemented in
 In python, modules are first class objects. This means can store them as values or add them to dicts or other modules:
 
 ```rust
+use pyo3::prelude::*;
+use pyo3::{wrap_pyfunction, wrap_pymodule};
+use pyo3::types::PyDict;
+
 #[pyfunction]
+#[cfg(Py_3)]
 fn subfunction() -> String {
     "Subfunction".to_string()
 }
 
 #[pymodule]
+#[cfg(Py_3)]
 fn submodule(_py: Python, module: &PyModule) -> PyResult<()> {
     module.add_wrapped(wrap_pyfunction!(subfunction))?;
     Ok(())
 }
 
 #[pymodule]
+#[cfg(Py_3)]
 fn supermodule(_py: Python, module: &PyModule) -> PyResult<()> {
     module.add_wrapped(wrap_pymodule!(submodule))?;
     Ok(())
 }
 
+#[cfg(Py_3)]
 fn nested_call() {
     let gil = GILGuard::acquire();
     let py = gil.python();
     let supermodule = wrap_pymodule!(supermodule)(py);
+    let ctx = PyDict::new(py);
     ctx.set_item("supermodule", supermodule);
 
     py.run("assert supermodule.submodule.subfuntion() == 'Subfunction'", None, Some(&ctx)).unwrap();