How I can secure my Python code , so other can not read it ?

If you want to prevent others from reading your Python code, you can use a technique called "code obfuscation". 

Code obfuscation is the process of making your code difficult to understand or read without affecting its functionality. This can be achieved by using tools that scramble or rename variable names, function and module names, as well as making the code structure more complex.

Here are some popular Python obfuscation tools that you can use:

1. Pyminifier: It's an open-source Python code minifier, which reduces the size of your code and makes it harder to read by removing unnecessary whitespace, comments, and replacing long variable names with shorter ones.

2. Pyarmor: It's another open-source obfuscator that allows you to encrypt your Python code and control access to your program through licensing features. Pyarmor can also add tamper resistance to your code by checking for modifications at runtime.

3. PyObfuscate: It's a commercial obfuscator that renames variables, adds fake code to confuse decompilers, and allows you to control access to specific parts of your code.

4. Cython: It's a tool that allows you to compile your Python code into C code, which can then be compiled into an executable binary. This process can make reverse engineering more difficult, but keep in mind that it won't completely protect your code.

It's important to note that code obfuscation is not a bulletproof solution, and experienced attackers can still reverse-engineer your code. Therefore, it's essential to follow other security measures mentioned earlier, such as code signing and access control, to ensure the overall security of your application.