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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def install_user_command_legacy(command, **substitutions):
    '''Install command executable file into users bin dir.

    If a custom executable exists it would be installed instead of the "normal"
    one.  The executable also could exist as a <command>.template file.
    '''
    path = flo('~/bin/{command}')
    install_file_legacy(path, **substitutions)
    run(flo('chmod 755 {path}'))