Changes from comments on PR #2288

- Add a test to make sure a tuple with a single module class still works for backwards compatibility.
- Take out the docstring examples for `attach_module()` and leave them only in the docs. The consensus is that lengthy docstrings reiterating what is in the documentation would just crowd out our files and make the code harder to read. Instead, we should opt for brief yet useful despritions in the method docstrings.

tests/core/utilities/test_attach_modules.py

@@ -53,6 +53,11 @@ def test_attach_modules():
     assert w3.geth.admin.start_ws() is True
 
 
+def test_attach_single_module_as_tuple():
+    w3 = Web3(EthereumTesterProvider(), modules={'eth': (MockEth,)})
+    assert w3.eth.block_number() == 42
+
+
 def test_attach_modules_multiple_levels_deep():
     mods = {
         "eth": MockEth,

web3/main.py

@@ -339,28 +339,6 @@ def attach_module(
         """
         Attach a module to the `Web3` instance. Modules should inherit from the `web3.module.Module`
         class.
-
-        Attaching a simple module:
-
-            >>> w3.attach_module('module1', ModuleClass1)
-            >>> w3.module1.return_zero
-            0
-
-        Attaching a module with submodules:
-
-            >>> w3.attach_module(
-            ...     'module2',
-            ...     (ModuleClass2, {
-            ...         'submodule1': ModuleClass3,
-            ...         'submodule2': (ModuleClass4, {
-            ...             'submodule2a': ModuleClass5,
-            ...         })
-            ...     })
-            ... )
-            >>> w3.module2.submodule1.return_one
-            1
-            >>> w3.module2.submodule2.submodule2a.return_two
-            2
         """
         attach_modules(self, {module_name: module})