Fix crash on open caused by incorrect conditional in python module

modules/python/init.zsh

@@ -114,14 +114,18 @@ if (( $+VIRTUALENVWRAPPER_VIRTUALENV || $+commands[virtualenv] )) \
     pyenv_plugins=(${(@oM)${(f)"$(pyenv commands --no-sh 2> /dev/null)"}:#virtualenv*})
   fi
 
+  # Optionally activate 'virtualenv' plugin when available.
   if (( $pyenv_plugins[(i)virtualenv-init] <= $#pyenv_plugins )); then
-    # Enable 'virtualenv' with 'pyenv'.
     eval "$(pyenv virtualenv-init - zsh)"
+  fi
 
   # Optionally activate 'virtualenvwrapper' plugin when available.
   if (( $pyenv_plugins[(i)virtualenvwrapper(_lazy|)] <= $#pyenv_plugins )); then
     pyenv "$pyenv_plugins[(R)virtualenvwrapper(_lazy|)]"
   fi
+  
+  unset pyenv_plugins
+  
 else
   # Fallback to 'virtualenvwrapper' without 'pyenv' wrapper if 'python' is
   # available in '$path'.
@@ -140,9 +144,6 @@ if (( $+VIRTUALENVWRAPPER_VIRTUALENV || $+commands[virtualenv] )) \
   unset virtenv_sources
 fi
 
-  unset pyenv_plugins
-fi
-
 # Load conda into the shell session, if requested.
 zstyle -T ':prezto:module:python' conda-init
 if (( $? && $+commands[conda] )); then