gistfile1.txt

class Copy(object):
    def __init__(self, builder):
        pass

    def __str__(self):
        return ''

class Builder(object):
    def __init__(self):
        self._native_commands = []

    def add_native(self, cmd):
        self._native_commands.append(cmd)
        return self

    

    def to_docker(self):
        return ''


d = Builder().
        add_native(Copy).
        add_native(Copy).
        add_native(Run).
        add_native...
        .set_distro(Distro('centos7', 7).
                     add_repo().
                     add_repo().
                     )