To install cx_Oracle on Red Hat Linux

# yum search python-dev
...
python-devel.i686 : The libraries and header files needed for Python development
python-devel.x86_64 : The libraries and header files needed for Python development

# file /usr/bin/python
/usr/bin/python: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs)

# yum install python-devel.x86_64

# pip install cx_Oracle

$ export ORACLE_HOME=...
$ export LD_LIBRARY_PATH=$ORACLE_HOME/lib
$ python -c 'import cx_Oraclex'
$

$ cat test_conn.py
import cx_Oracle
con = cx_Oracle.connect('yong/mypwd@sanddb')
print con.version
con.close()
$ python test_conn.py
11.2.0.1.0