title: Tensorflow in r not found
body: <p>I have installed tensorflow in r with this code <code>install_tensorflow(conda_python_version = '3.8')</code>.
  When calling <code>tf$constant('Hellow Tensorflow')</code>, I get this error:</p>
  <pre><code>Error: Installation of TensorFlow not found.
  
  Python environments searched for 'tensorflow' package:
   C:\Users\User\.conda\envs\r-reticulate\python.exe
   C:\ProgramData\Anaconda3\python.exe
  
  You can install TensorFlow using the install_tensorflow() function.
  </code></pre>
  <p>However, I have the python.exe in the first location and have the library in <code>C:\Users\User\.conda\envs\r-reticulate\Lib\site-packages\tensorflow\</code>. Why the tensorflow installation could not be found?</p>