title: Conda create an envrioment py3.7 with only installing jupyter, but founds conflict
body: <p>When I created a new environment like this: <code>conda create -n nb python=3.7 jupyter</code> , it failed.</p>
  
  <p>The console told me:</p>
  
  <pre><code>Collecting package metadata (current_repodata.json): done
  Solving environment: failed with repodata from current_repodata.json, will retry with next repodata source.
  Collecting package metadata (repodata.json): done
  Solving environment: /
  Found conflicts! Looking for incompatible packages.
  This can take several minutes.  Press CTRL-C to abort.-
  Examining jupyter: 100%|████████████████████████████████████████████████failed
  
  UnsatisfiableError: The following specifications were found to be incompatible with each other:
  
  Output in format: Requested package -&gt; Available versions
  
  Package python conflicts for:
  python=3.7
  jupyter -&gt; python[version='2.7.*|3.4.*|3.5.*|3.6.*|&gt;=2.7,&lt;2.8.0a0|&gt;=3.5,&lt;3.6.0a0|&gt;=3.8,&lt;3.9.0a0|&gt;=3.6,&lt;3.7.0a0|&gt;=3.7,&lt;3.8.0a0']
  jupyter -&gt; ipywidgets -&gt; python[version='&gt;=3.5']
  </code></pre>
  
  <p>so I went to the base enviroment to check the installed packages for their versions. <code>(base) D:\&gt;conda list</code></p>
  
  <p>the python version is 3.7.4, and the jupyter is 1.0.0. So I tried again. <code>conda create -n nb python=3.7.3 jupyter=1.0.0</code> </p>
  
  <p>Yet, it still cannot work. I'm very confused. Why??</p>
  
  <p>Here is the <code>conda info</code></p>
  
  <pre><code>     active environment : base
      active env location : C:\ProgramData\Anaconda3
              shell level : 1
         user config file : C:\Users\Administrator\.condarc
   populated config files : C:\Users\Administrator\.condarc
            conda version : 4.8.2
      conda-build version : 3.18.9
           python version : 3.7.4.final.0
         virtual packages :
         base environment : C:\ProgramData\Anaconda3  (writable)
             channel URLs : https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/win-64
                            https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/noarch
                            https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/win-64
                            https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/noarch
                            https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/r/win-64
                            https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/r/noarch
            package cache : C:\ProgramData\Anaconda3\pkgs
                            C:\Users\Administrator\.conda\pkgs
                            C:\Users\Administrator\AppData\Local\conda\conda\pkgs
         envs directories : C:\ProgramData\Anaconda3\envs
                            C:\Users\Administrator\.conda\envs
                            C:\Users\Administrator\AppData\Local\conda\conda\envs
                 platform : win-64
               user-agent : conda/4.8.2 requests/2.22.0 CPython/3.7.4 Windows/10 Windows/10.0.18362
            administrator : True
               netrc file : None
             offline mode : False
  </code></pre>
  
  <p>I googled, but it seems noboday has got the problem like me. Why does this have to just happen to me.</p>
  
  <p>please, I need some help.</p>