Example of how a twister/swizzler/etc. installer could look with npyscreen

example_installer.py

import npyscreen

class TestInstaller(npyscreen.NPSApp):
    def main(self):
        # These lines create the form and populate it with widgets.
        # A fairly complex screen in only 8 or so lines of code - a line for each control.
        f  = npyscreen.Form(name="Example installer: edit an RPC url",)
        fields = {
            'username':f.add(npyscreen.TitleText, name="Username:"),
            'password':f.add(npyscreen.TitlePassword, name="Password:"),
            'protocol':f.add(npyscreen.TitleSelectOne, name="RPC protocol",
                values = ["http","https"], max_height=2, value=[0], scroll_exit=True),
            'host':f.add(npyscreen.TitleText, value='127.0.0.1', name="RPC host:"),
            'port':f.add(npyscreen.TitleText, value='28332', name="RPC port:"),
        }
        messages = ['This is an example installer.','It constructs an RPC url.','Enjoy.']
        while messages:
            npyscreen.notify_confirm('\n'.join(messages),'Example installer')
            messages = []
            f.edit()
            if len(fields['username'].value.strip())<3: #LOL, I just wrote <3
                messages.append('Username missing or too short') # just an example bs validation method
            if len(fields['password'].value.strip())<8:
                messages.append('Password missing or too short') # just an example bs validation method
        
        result = {}
        for k in fields:
            v = fields[k].value
            result[k] = type(v)==type([]) and fields[k].values[v[0]].strip() or v.strip()
        npyscreen.notify_confirm(
            "{protocol}://{username}:{password}@{host}:{port}".format(**result),
            "This is the RPC url (just sayin')")

if __name__ == "__main__":
    App = TestInstaller()
    App.run()

screenshot.png