libxml/xmlversion.h: No such file or directory

/tmp/pip-build-imUeln/lxml/src/lxml/includes/etree_defs.h:14:31: fatal error: libxml/xmlversion.h: No such file or directory
    
     #include "libxml/xmlversion.h"
    
                                   ^
    
    compilation terminated.
    

    error: command 'gcc' failed with exit status 1

解决：

export C_INCLUDE_PATH=/usr/include/libxml2/

仍发生错误：

ERROR: /bin/sh: xslt-config: command not found   
    
    
    ** make sure the development packages of libxml2 and libxslt are installed **

/tmp/pip-build-l1hWXy/lxml/src/lxml/includes/etree_defs.h:23:32: fatal error: libxslt/xsltconfig.h: No such file or directory
     #include "libxslt/xsltconfig.h"
                                    ^
    compilation terminated.
    error: command 'gcc' failed with exit status 1

解决：yum install libxslt-devel

再安装pip install lxml 或 scrapy 成功。

Successfully installed lxml-3.4.2 scrapy-0.24.5