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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 close(self):
 """Close the file that contains the Group. All groups which are in the file will be closed and removed from the _instances dictionaries. Tempfiles, if they exist, will be removed """

        from .collection import Collection
        from .data._data import Channel, Data, Variable

        path = os.path.abspath(self.filepath) + "::"
        for key in list(Group._instances.keys()):
            if key.startswith(path):
                Group._instances.pop(key, None)

        if self.fid.valid > 0:
            # for some reason, the following file operations sometimes fail
            # this stops execution of the method, meaning that the tempfile is never removed
            # the following try case ensures that the tempfile code is always executed
            # ---Blaise 2018-01-08
            try:
                self.file.flush()
                try:
                    # Obtaining the file descriptor must be done prior to closing
                    fd = self.fid.get_vfd_handle()
                except (NotImplementedError, ValueError):
                    # only available with certain h5py drivers
                    # not needed if not available
                    pass

                self.file.close()
                try:
                    if fd:
                        os.close(fd)
                except OSError:
                    # File already closed, e.g.
                    pass
            except SystemError as e:
                warnings.warn("SystemError: {0}".format(e))
            finally:
                if hasattr(self, "_tmpfile"):
                    os.close(self._tmpfile[0])
                    os.remove(self._tmpfile[1])