remove Python 2 from docs

docs/patterns/distribute.rst

@@ -19,10 +19,6 @@ complex constructs that make larger applications easier to distribute:
   other package.
 - **installation manager**: :command:`pip` can install other libraries for you.
 
-If you have Python 2 (>=2.7.9) or Python 3 (>=3.4) installed from python.org,
-you will already have pip and setuptools on your system.  Otherwise, you
-will need to install them yourself.
-
 Flask itself, and all the libraries you can find on PyPI are distributed with
 either setuptools or distutils.
 

docs/patterns/sqlalchemy.rst

@@ -39,7 +39,7 @@ Here's the example :file:`database.py` module for your application::
     from sqlalchemy.orm import scoped_session, sessionmaker
     from sqlalchemy.ext.declarative import declarative_base
 
-    engine = create_engine('sqlite:////tmp/test.db', convert_unicode=True)
+    engine = create_engine('sqlite:////tmp/test.db')
     db_session = scoped_session(sessionmaker(autocommit=False,
                                              autoflush=False,
                                              bind=engine))
@@ -127,7 +127,7 @@ Here is an example :file:`database.py` module for your application::
     from sqlalchemy import create_engine, MetaData
     from sqlalchemy.orm import scoped_session, sessionmaker
 
-    engine = create_engine('sqlite:////tmp/test.db', convert_unicode=True)
+    engine = create_engine('sqlite:////tmp/test.db')
     metadata = MetaData()
     db_session = scoped_session(sessionmaker(autocommit=False,
                                              autoflush=False,
@@ -179,7 +179,7 @@ you basically only need the engine::
 
     from sqlalchemy import create_engine, MetaData, Table
 
-    engine = create_engine('sqlite:////tmp/test.db', convert_unicode=True)
+    engine = create_engine('sqlite:////tmp/test.db')
     metadata = MetaData(bind=engine)
 
 Then you can either declare the tables in your code like in the examples

docs/patterns/wtforms.rst

@@ -98,9 +98,9 @@ This macro accepts a couple of keyword arguments that are forwarded to
 WTForm's field function, which renders the field for us.  The keyword
 arguments will be inserted as HTML attributes.  So, for example, you can
 call ``render_field(form.username, class='username')`` to add a class to
-the input element.  Note that WTForms returns standard Python unicode
-strings, so we have to tell Jinja2 that this data is already HTML-escaped
-with the ``|safe`` filter.
+the input element.  Note that WTForms returns standard Python strings,
+so we have to tell Jinja2 that this data is already HTML-escaped with
+the ``|safe`` filter.
 
 Here is the :file:`register.html` template for the function we used above, which
 takes advantage of the :file:`_formhelpers.html` template: