diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index a71f6fe0..93ab2e6d 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,24 +1,28 @@
 repos:
 -   repo: git://github.com/pre-commit/pre-commit-hooks
-    rev: v1.3.0
+    rev: v2.1.0
     hooks:
+    -   id: check-merge-conflict
     -   id: check-json
     -   id: check-yaml
     -   id: debug-statements
     -   id: end-of-file-fixer
         exclude: ^docs/.*$
-    -   id: trailing-whitespace
-        exclude: README.md
     -   id: pretty-format-json
         args:
         - --autofix
-    -   id: flake8
+    -   id: trailing-whitespace
+        exclude: README.md
 -   repo: https://github.com/asottile/pyupgrade
-    rev: v1.4.0
+    rev: v1.12.0
     hooks:
     -   id: pyupgrade
 -   repo: https://github.com/ambv/black
-    rev: 18.6b4
+    rev: 18.9b0
     hooks:
     - id: black
       language_version: python3
+-   repo: https://github.com/PyCQA/flake8
+    rev: 3.7.7
+    hooks:
+    -   id: flake8
diff --git a/CODEOWNERS b/CODEOWNERS
new file mode 100644
index 00000000..26bb1aff
--- /dev/null
+++ b/CODEOWNERS
@@ -0,0 +1 @@
+/ @syrusakbary @ekampf @dan98765 @projectcheshire
diff --git a/UPGRADE-v2.0.md b/UPGRADE-v2.0.md
index 32b28d8b..d9d48005 100644
--- a/UPGRADE-v2.0.md
+++ b/UPGRADE-v2.0.md
@@ -17,7 +17,7 @@ developer has to write to use them.
 
 **New Features!**
 * [`InputObjectType`](#inputobjecttype)
-* [`Meta as Class arguments`](#meta-ass-class-arguments) (_only available for Python 3_)
+* [`Meta as Class arguments`](#meta-as-class-arguments) (_only available for Python 3_)
 
 
 > The type metaclasses are now deleted as they are no longer necessary.  If your code was depending
@@ -276,7 +276,7 @@ If you are using Middelwares, you need to some adjustments:
 Before:
 
 ```python
-class MyGrapheneMiddleware(object):  
+class MyGrapheneMiddleware(object):
     def resolve(self, next_mw, root, args, context, info):
 
         ## Middleware code
@@ -287,7 +287,7 @@ class MyGrapheneMiddleware(object):
 With 2.0:
 
 ```python
-class MyGrapheneMiddleware(object):  
+class MyGrapheneMiddleware(object):
     def resolve(self, next_mw, root, info, **args):
         context = info.context
 
diff --git a/docs/types/objecttypes.rst b/docs/types/objecttypes.rst
index ca0d6b3f..b6eb3087 100644
--- a/docs/types/objecttypes.rst
+++ b/docs/types/objecttypes.rst
@@ -25,8 +25,8 @@ This example model defines a Person, with a first and a last name:
         last_name = graphene.String()
         full_name = graphene.String()
 
-        def resolve_full_name(self, info):
-            return '{} {}'.format(self.first_name, self.last_name)
+        def resolve_full_name(root, info):
+            return '{} {}'.format(root.first_name, root.last_name)
 
 **first\_name** and **last\_name** are fields of the ObjectType. Each
 field is specified as a class attribute, and each attribute maps to a
@@ -56,23 +56,148 @@ NOTE: The resolvers on an ``ObjectType`` are always treated as ``staticmethod``\
 so the first argument to the resolver method ``self`` (or ``root``) need
 not be an actual instance of the ``ObjectType``.
 
+If an explicit resolver is not defined on the ``ObjectType`` then Graphene will
+attempt to use a property with the same name on the object that is passed to the
+``ObjectType``.
 
-Quick example
-~~~~~~~~~~~~~
+.. code:: python
 
-This example model defines a ``Query`` type, which has a reverse field
-that reverses the given ``word`` argument using the ``resolve_reverse``
-method in the class.
+    import graphene
+
+    class Person(graphene.ObjectType):
+        first_name = graphene.String()
+        last_name = graphene.String()
+
+    class Query(graphene.ObjectType):
+        me = graphene.Field(Person)
+
+        def resolve_me(_, info):
+            # returns an object that represents a Person
+            return get_human(name='Luke Skywalker')
+
+If you are passing a dict instead of an object to your ``ObjectType`` you can
+change the default resolver in the ``Meta`` class like this:
+
+.. code:: python
+
+    import graphene
+    from graphene.types.resolver import dict_resolver
+
+    class Person(graphene.ObjectType):
+        class Meta:
+            default_resolver = dict_resolver
+
+        first_name = graphene.String()
+        last_name = graphene.String()
+
+    class Query(graphene.ObjectType):
+        me = graphene.Field(Person)
+
+        def resolve_me(_, info):
+            return {
+                "first_name": "Luke",
+                "last_name": "Skywalker",
+            }
+
+Or you can change the default resolver globally by calling ``set_default_resolver``
+before executing a query.
+
+.. code:: python
+
+    import graphene
+    from graphene.types.resolver import dict_resolver, set_default_resolver
+
+    set_default_resolver(dict_resolver)
+
+    schema = graphene.Schema(query=Query)
+    result = schema.execute('''
+        query {
+            me {
+                firstName
+            }
+        }
+     ''')
+
+
+Resolvers with arguments
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Any arguments that a field defines gets passed to the resolver function as
+kwargs. For example:
 
 .. code:: python
 
     import graphene
 
     class Query(graphene.ObjectType):
-        reverse = graphene.String(word=graphene.String())
+        human_by_name = graphene.Field(Human, name=graphene.String(required=True))
+
+        def resolve_human_by_name(_, info, name):
+            return get_human(name=name)
+
+You can then execute the following query:
+
+.. code::
+
+    query {
+        humanByName(name: "Luke Skywalker") {
+            firstName
+            lastName
+        }
+    }
+
+NOTE: if you define an argument for a field that is not required (and in a query
+execution it is not provided as an argument) it will not be passed to the
+resolver function at all. This is so that the developer can differenciate
+between a ``undefined`` value for an argument and an explicit ``null`` value.
+
+For example, given this schema:
+
+.. code:: python
+
+    import graphene
+
+    class Query(graphene.ObjectType):
+        hello = graphene.String(required=True, name=graphene.String())
+
+        def resolve_hello(_, info, name):
+            return name if name else 'World'
+
+And this query:
+
+.. code::
+
+    query {
+        hello
+    }
+
+An error will be thrown:
+
+.. code::
+
+    TypeError: resolve_hello() missing 1 required positional argument: 'name'
+
+You can fix this error in 2 ways. Either by combining all keyword arguments
+into a dict:
+
+.. code:: python
+
+    class Query(graphene.ObjectType):
+        hello = graphene.String(required=True, name=graphene.String())
+
+        def resolve_hello(_, info, **args):
+            return args.get('name', 'World')
+
+Or by setting a default value for the keyword argument:
+
+.. code:: python
+
+    class Query(graphene.ObjectType):
+        hello = graphene.String(required=True, name=graphene.String())
+
+        def resolve_hello(_, info, name='World'):
+            return name
 
-        def resolve_reverse(self, info, word):
-            return word[::-1]
 
 Resolvers outside the class
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -83,11 +208,13 @@ A field can use a custom resolver from outside the class:
 
     import graphene
 
-    def reverse(root, info, word):
-        return word[::-1]
+    def resolve_full_name(person, info):
+        return '{} {}'.format(person.first_name, person.last_name)
 
-    class Query(graphene.ObjectType):
-        reverse = graphene.String(word=graphene.String(), resolver=reverse)
+    class Person(graphene.ObjectType):
+        first_name = graphene.String()
+        last_name = graphene.String()
+        full_name = graphene.String(resolver=resolve_full_name)
 
 
 Instances as data containers
diff --git a/graphene/pyutils/signature.py b/graphene/pyutils/signature.py
index c66c2563..7757d9d0 100644
--- a/graphene/pyutils/signature.py
+++ b/graphene/pyutils/signature.py
@@ -707,7 +707,10 @@ class Signature(object):
                         break
                     elif param.name in kwargs:
                         if param.kind == _POSITIONAL_ONLY:
-                            msg = "{arg!r} parameter is positional only, " "but was passed as a keyword"
+                            msg = (
+                                "{arg!r} parameter is positional only, "
+                                "but was passed as a keyword"
+                            )
                             msg = msg.format(arg=param.name)
                             raise TypeError(msg)
                         parameters_ex = (param,)
diff --git a/graphene/types/argument.py b/graphene/types/argument.py
index 9c75bcee..bf304608 100644
--- a/graphene/types/argument.py
+++ b/graphene/types/argument.py
@@ -75,9 +75,7 @@ def to_arguments(args, extra_args=None):
         arg_name = default_name or arg.name
         assert (
             arg_name not in arguments
-        ), 'More than one Argument have same name "{}".'.format(
-            arg_name
-        )
+        ), 'More than one Argument have same name "{}".'.format(arg_name)
         arguments[arg_name] = arg
 
     return arguments
diff --git a/graphene/types/base.py b/graphene/types/base.py
index aa97ed22..75685d98 100644
--- a/graphene/types/base.py
+++ b/graphene/types/base.py
@@ -1,5 +1,9 @@
 from ..utils.subclass_with_meta import SubclassWithMeta
 from ..utils.trim_docstring import trim_docstring
+import six
+
+if six.PY3:
+    from typing import Type
 
 
 class BaseOptions(object):
diff --git a/graphene/types/scalars.py b/graphene/types/scalars.py
index dfb63e52..c5f43787 100644
--- a/graphene/types/scalars.py
+++ b/graphene/types/scalars.py
@@ -4,6 +4,9 @@ from graphql.language.ast import BooleanValue, FloatValue, IntValue, StringValue
 from .base import BaseOptions, BaseType
 from .unmountedtype import UnmountedType
 
+if six.PY3:
+    from typing import Any
+
 
 class ScalarOptions(BaseOptions):
     pass
diff --git a/graphene/types/tests/test_definition.py b/graphene/types/tests/test_definition.py
index 347de9c9..549847d5 100644
--- a/graphene/types/tests/test_definition.py
+++ b/graphene/types/tests/test_definition.py
@@ -1,5 +1,3 @@
-
-
 from ..argument import Argument
 from ..enum import Enum
 from ..field import Field
diff --git a/graphene/types/tests/test_inputobjecttype.py b/graphene/types/tests/test_inputobjecttype.py
index d565ff40..dc557b94 100644
--- a/graphene/types/tests/test_inputobjecttype.py
+++ b/graphene/types/tests/test_inputobjecttype.py
@@ -1,4 +1,3 @@
-
 from ..argument import Argument
 from ..field import Field
 from ..inputfield import InputField
diff --git a/graphene/types/tests/test_json.py b/graphene/types/tests/test_json.py
index 6b8189c4..b5537180 100644
--- a/graphene/types/tests/test_json.py
+++ b/graphene/types/tests/test_json.py
@@ -1,4 +1,3 @@
-
 from ..json import JSONString
 from ..objecttype import ObjectType
 from ..schema import Schema
diff --git a/graphene/types/tests/test_mountedtype.py b/graphene/types/tests/test_mountedtype.py
index 787bee56..b964233e 100644
--- a/graphene/types/tests/test_mountedtype.py
+++ b/graphene/types/tests/test_mountedtype.py
@@ -1,4 +1,3 @@
-
 from ..field import Field
 from ..scalars import String
 
diff --git a/graphene/types/tests/test_resolver.py b/graphene/types/tests/test_resolver.py
index 3be9a492..2a15028d 100644
--- a/graphene/types/tests/test_resolver.py
+++ b/graphene/types/tests/test_resolver.py
@@ -1,4 +1,3 @@
-
 from ..resolver import (
     attr_resolver,
     dict_resolver,
diff --git a/graphene/types/tests/test_scalar.py b/graphene/types/tests/test_scalar.py
index 1ec986cd..559c0ce6 100644
--- a/graphene/types/tests/test_scalar.py
+++ b/graphene/types/tests/test_scalar.py
@@ -1,4 +1,3 @@
-
 from ..scalars import Scalar
 
 
diff --git a/graphene/utils/str_converters.py b/graphene/utils/str_converters.py
index d8804038..216b0547 100644
--- a/graphene/utils/str_converters.py
+++ b/graphene/utils/str_converters.py
@@ -18,4 +18,4 @@ def to_snake_case(name):
 
 
 def to_const(string):
-    return re.sub("[\W|^]+", "_", string).upper()
+    return re.sub(r"[\W|^]+", "_", string).upper()  # noqa
diff --git a/setup.py b/setup.py
index d9f62bec..48e5be35 100644
--- a/setup.py
+++ b/setup.py
@@ -1,4 +1,5 @@
 import ast
+import codecs
 import re
 import sys
 
@@ -61,7 +62,9 @@ setup(
     name="graphene",
     version=version,
     description="GraphQL Framework for Python",
-    long_description=open("README.rst").read(),
+    long_description=codecs.open(
+        "README.rst", "r", encoding="ascii", errors="replace"
+    ).read(),
     url="https://github.com/graphql-python/graphene",
     author="Syrus Akbary",
     author_email="me@syrusakbary.com",