You've got a few options.
- Update the current environment by installing python 3.6 into it. e.g.:
$ conda install python=3.6
Note that this will not work if you have any packages installed that are not python 3.6 compatible. If you do have conda packages that are not py3.6 compatible, you'll get errors like:
$ conda update --all python=3.6
Fetching package metadata .............
Solving package specifications: ....
UnsatisfiableError: The following specifications were found to be in conflict:
- enum34
- python 3.6*
Use "conda info <package>" to see the dependencies for each package.
And you'll need to go through and remove all of the offending packages.
Another option is to create a new conda environment with python 3.6 and spyder (and any other dependencies that you need).
$ conda create -n py36 python=3.6 spyder ..
$ source activate py36
$ spyder
Final option is to remove your conda folder and then reinstall anaconda with python 3.6 or miniconda with python 3.6.