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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 _set_mpl_backend(self, backend, pylab=False):
 """ Set a backend for Matplotlib. backend: A parameter that can be passed to %matplotlib (e.g. 'inline' or 'tk'). """

        import traceback
        from IPython.core.getipython import get_ipython

        generic_error = (
            "\n" + "="*73 + "\n"
            "NOTE: The following error appeared when setting "
            "your Matplotlib backend!!\n" + "="*73 + "\n\n"
            "{0}"
        )

        magic = 'pylab' if pylab else 'matplotlib'

        error = None
        try:
            get_ipython().run_line_magic(magic, backend)
        except RuntimeError as err:
            # This catches errors generated by ipykernel when
            # trying to set a backend. See issue 5541
            if "GUI eventloops" in str(err):
                import matplotlib
                previous_backend = matplotlib.get_backend()
                if not backend in previous_backend.lower():
                    # Only inform about an error if the user selected backend
                    # and the one set by Matplotlib are different. Else this
                    # message is very confusing.
                    error = (
                        "\n"
                        "NOTE: Spyder *can't* set your selected Matplotlib "
                        "backend because there is a previous backend already "
                        "in use.\n\n"
                        "Your backend will be {0}".format(previous_backend)
                    )
                del matplotlib
            # This covers other RuntimeError's
            else:
                error = generic_error.format(traceback.format_exc())
        except Exception:
            error = generic_error.format(traceback.format_exc())

        self._mpl_backend_error = error