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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 vim_ipython_is_open():
 """ Helper function to let us know if the vim-ipython shell is currently visible """

    for w in vim.windows:
        if w.buffer.name is not None and w.buffer.name.endswith("vim-ipython"):
            return True
    return False