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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 _prompt_changer(attr, val):
 """Change the current prompt theme"""

    try:
        sys.ps1 = conf.color_theme.prompt(conf.prompt)
    except Exception:
        pass
    try:
        apply_ipython_style(get_ipython())
    except NameError:
        pass