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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 convert_ipynbs(directory):
 """Recursively converts all ipynb files in a directory into rst files in the same directory."""

    # The ipython_examples dir has to be in the same dir as this script
    for root, subfolders, files in os.walk(os.path.abspath(directory)):
        for f in files:
            if ".ipynb_checkpoints" not in root:
                if f.endswith("ipynb"):
                    ipynb_to_rst(root, f)