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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 gen_binder_rst(fpath, binder_conf, gallery_conf):
 """Generate the RST + link for the Binder badge. Parameters fpath: str The path to the `.py` file for which a Binder badge will be generated. binder_conf: dict or None If a dictionary it must have the following keys: 'binderhub_url': The URL of the BinderHub instance that's running a Binder service. 'org': The GitHub organization to which the documentation will be pushed. 'repo': The GitHub repository to which the documentation will be pushed. 'branch': The Git branch on which the documentation exists (e.g., gh-pages). 'dependencies': A list of paths to dependency files that match the Binderspec. Returns ------- rst : str The reStructuredText for the Binder badge that links to this file. """

    binder_conf = check_binder_conf(binder_conf)
    binder_url = gen_binder_url(fpath, binder_conf, gallery_conf)

    rst = (
        "\n"
        "  .. container:: binder-badge\n\n"
        "    .. image:: https://mybinder.org/badge_logo.svg\n"
        "      :target: {}\n"
        "      :width: 150 px\n").format(binder_url)
    return rst