Is libxml2 installed?

1. Could not find function xmlCheckVersion in library libxml2. Is libxml2 installed?

   building 'lxml.etree' extension
   creating build/temp.linux-x86_64-2.7
   creating build/temp.linux-x86_64-2.7/src
   creating build/temp.linux-x86_64-2.7/src/lxml
   gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -Isrc/lxml/includes -I/usr/include/python2.7 -c src/lxml/lxml.etree.c -o build/temp.linux-x86_64-2.7/src/lxml/lxml.etree.o -w
   In file included from src/lxml/lxml.etree.c:320:0:
   src/lxml/includes/etree_defs.h:14:31: fatal error: libxml/xmlversion.h: 没有那个文件或目录
   compilation terminated.
   Compile failed: command 'gcc' failed with exit status 1
   cc -I/usr/include/libxml2 -c /tmp/xmlXPathInitshtn_t.c -o tmp/xmlXPathInitshtn_t.o
   /tmp/xmlXPathInitshtn_t.c:1:26: fatal error: libxml/xpath.h: 没有那个文件或目录
   compilation terminated.
   *
   Could not find function xmlCheckVersion in library libxml2. Is libxml2 installed?
   *
   error: command 'gcc' failed with exit status 1

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sudo apt-get install libxml2-dev libxslt1-dev python-dev
and

apt-get install libxml2-dev libxslt1-dev python-dev