Python version 2.7， which was not found in the registry

在安装部分Python包时会出现问题：明明已经安装了Python2.7，但无法在注册表相关位置找不到，那该怎么感觉该问题呢？

首先检查你的系统位数，位数不同，解决方案不一样。

1）32位系统：在cmd输入regedit然后将HKEY_LOCAL_MACHINE\SOFTWARE\Python\PythonCore\2.7\InstallPath路径下的值，复制到HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Python\PythonCore\2.7\InstallPath路径下，当然没有路径的话一定要新建起来。然后就可以安装了。本解决方案适用于只提供了32位安装包的库。

原因：Python的一些第三方库只到注册表的HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Python\PythonCore\2.7\InstallPath路径下寻找Python。但是装好的64位Python在HKEY_LOCAL_MACHINE\SOFTWARE\Python\PythonCore\2.7\InstallPath路径下建立Python的信息。

2）64位系统：将Python2.7加入到注册表中。可以通过运行下面代码：

 import sys
 
 from _winreg import *
 
 # tweak as necessary
 version = sys.version[:3]
 installpath = sys.prefix
 regpath = "SOFTWARE\\Python\\Pythoncore\\%s\\" % (version)
 installkey = "InstallPath"
 pythonkey = "PythonPath"
 pythonpath = "%s;%s\\Lib\\;%s\\DLLs\\" % (
 installpath, installpath, installpath
 )
 
 def RegisterPy():
     print "begin RegisterPy "
     try:
         print "open key : %s"%regpath
         reg = OpenKey(HKEY_CURRENT_USER, regpath)
     except EnvironmentError as e:
         try:
             reg = CreateKey(HKEY_CURRENT_USER, regpath)
             SetValue(reg, installkey, REG_SZ, installpath)
             SetValue(reg, pythonkey, REG_SZ, pythonpath)
             CloseKey(reg)
         except:
             print "*** EXCEPT: Unable to register!"
             return             
 
         print "--- Python", version, "is now registered!"
         return
 
     if (QueryValue(reg, installkey) == installpath and
         QueryValue(reg, pythonkey) == pythonpath):
             CloseKey(reg)
             print "=== Python", version, "is already registered!"
             return CloseKey(reg) 
 
     print "*** ERROR:Unable to register!"
     print "*** REASON:You probably have another Python installation!"
 
 def UnRegisterPy():
     #print "begin UnRegisterPy "
     try:
         print "open HKEY_CURRENT_USER key=%s"%(regpath)
         reg = OpenKey(HKEY_CURRENT_USER, regpath)
         #reg = OpenKey(HKEY_LOCAL_MACHINE, regpath)
     except EnvironmentError:
         print "*** Python not registered?!"
         return
     try:
        DeleteKey(reg, installkey)
        DeleteKey(reg, pythonkey)
        DeleteKey(HKEY_LOCAL_MACHINE, regpath)
     except:
        print "*** Unable to un-register!"
     else:
        print "--- Python", version, "is no longer registered!"            
 
 if __name__ == "__main__":
     RegisterPy()