any way to tell if user's python environment is anaconda

I'm from Continuum, so let me make a quick note: You'll get a different sys.version string depending on whether you used conda to install the Anaconda Python Distribution or simply Python. So from conda create -n full_apd anaconda you'd get a sys.version string as follows:

$ python -c "import sys; print sys.version"
2.7.6 |Anaconda 1.8.0 (x86_64)| (default, Jan 10 2014, 11:23:15) 
[GCC 4.0.1 (Apple Inc. build 5493)]

This is what you get if you use miniconda or are working from a conda environment where you have just specified python (e.g. conda create -n base_py27 python=2.7):

$ python -c "import sys; print sys.version"
2.7.6 |Continuum Analytics, Inc.| (default, Jan 10 2014, 11:23:15) 
[GCC 4.0.1 (Apple Inc. build 5493)]

If you have simply downloaded and installed the full Anaconda Python Distribution directly, you'll get the former:

$ python -c "import sys; print sys.version"
2.7.6 |Anaconda 1.8.0 (x86_64)| (default, Jan 10 2014, 11:23:15) 
[GCC 4.0.1 (Apple Inc. build 5493)]

In [109]: import sys

In [110]: 'conda' in sys.version
Out[110]: True

For version > 3.7, the version info has changed like:

In [2]: sys.version
Out[2]: '3.7.1 (default, Dec 10 2018, 22:54:23) [MSC v.1915 64 bit (AMD64)]'

From this post The solution should be changed to:

import sys, os
is_conda = os.path.exists(os.path.join(sys.prefix, 'conda-meta'))

Documentation: http://docs.python.org/2/library/sys.html#sys.version

In [1]: import sys; sys.version
Out[1]: '2.7.5 |Anaconda 1.8.0 (64-bit)| (default, Jul  1 2013, 12:37:52) [MSC v.1500 64 bit (AMD64)]'