Move python_interpreter out of the config object

Move python_interpreter out of the config object

Author: agarwalrounak

readthedocs/config/config.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # pylint: disable=too-many-lines
 
 """Build configuration for rtd."""
@@ -37,6 +36,7 @@
     validate_string,
 )
 
+
 __all__ = (
     'ALL',
     'load',
@@ -233,11 +233,6 @@ def pop_config(self, key, default=None, raise_ex=False):
     def validate(self):
         raise NotImplementedError()
 
-    @property
-    def python_interpreter(self):
-        ver = self.python_full_version
-        return 'python{}'.format(ver)
-
     @property
     def python_full_version(self):
         ver = self.python.version
@@ -1093,6 +1088,11 @@ def submodules(self):
         return Submodules(**self._config['submodules'])
 
 
+def python_interpreter(self):
+    ver = self.python_full_version
+    return 'python{}'.format(ver)
+
+
 def load(path, env_config):
     """
     Load a project configuration and the top-most build config for a given path.