How to build the Boost Python for both Python2 and Python3?

I was trying to build the Boost 1.65.1 for both versions of Python I use:

./bootstrap.sh --with-python=python2 --with-python=python3

However, the first instance of the --with-python option has been ignored and I've got only /usr/local/lib/libboost_python3.* libraries.

So I've called the bootstrap in the same directory again with command:

./bootstrap.sh --with-python=python2

After that I've got both Boost Python libraries - for Python2 and Python3.

I've some doubts about this sequence of steps - the second step might damage results of the first one.

Are there any 100%-reliable ways to build the Boost Python (from sources) for both Python versions?

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