Tidy up documentation, and update code following advice from linter

Author: Mark Gibbs

django_plotly_dash/dash_wrapper.py

@@ -197,7 +197,7 @@ def before_first_request(self, *args, **kwargs):
         pass
     def run(self, *args, **kwargs):
         pass
-    def register_blueprint(*args, **kwargs):
+    def register_blueprint(self, *args, **kwargs):
         pass
 
 class WrappedDash(Dash):
@@ -415,6 +415,7 @@ def dispatch_with_args(self, body, argMap):
         return res
 
     def slugified_id(self):
+        'Return the app id in a slug-friendly form'
         pre_slugified_id = self._uid
         return slugify(pre_slugified_id)
 
@@ -436,4 +437,4 @@ def extra_html_properties(self, prefix=None, posfix=None, template_type=None):
                                                                                                          'post_part':post_part,
                                                                                                          'template_type':template_type,
                                                                                                          'prefix':prefix,
-                                                                                                         }
+                                                                                                        }

django_plotly_dash/templatetags/plotly_dash.py

@@ -75,6 +75,7 @@ def plotly_message_pipe(context, url=None):
 
 @register.simple_tag()
 def plotly_app_identifier(name=None, slug=None, da=None, postfix=None):
+    'Return a slug-friendly identifier'
     if name is not None:
         da, app = DashApp.locate_item(name, stateless=True)
 
@@ -92,6 +93,7 @@ def plotly_app_identifier(name=None, slug=None, da=None, postfix=None):
 
 @register.simple_tag()
 def plotly_class(name=None, slug=None, da=None, prefix=None, postfix=None, template_type=None):
+    'Return a string of space-separated class names'
 
     if name is not None:
         da, app = DashApp.locate_item(name, stateless=True)

docs/template_tags.rst

@@ -78,7 +78,9 @@ The tag arguments are:
 :da = None: An existing ``django_plotly_dash.models.DashApp`` model instance.
 :postfix = None: An optional string; if specified it is appended to the identifier with a hyphen.
 
-The validity rules for these arguments are the same as those for the ``plotly_app`` template tag.
+The validity rules for these arguments are the same as those for the ``plotly_app`` template tag. If
+supplied, the ``postfix`` argument
+should already be in a slug-friendly form, as no processing is performed on it.
 
 The ``plotly_class`` template tag
 -----------------------------------------
@@ -109,4 +111,6 @@ The tag inserts a string with three class names in it. One is just the ``prefix`
 has the ``template_type`` appended, and the final one has the app identifier (as generated
 by the ``plotly_app_identifier`` tag) and any ``postfix`` appended.
 
-The validity rules for these arguments are the same as those for the ``plotly_app`` template tag.
+The validity rules for these arguments are the same as those for the ``plotly_app``  and ``plotly_app_identifier`` template tags. Note
+that none of the ``prefix``, ``postfix`` and ``template_type`` arguments are modified and they should
+already be in a slug-friendly form, or otherwise fit for their intended purpose.