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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 write(self, data, groupname='h5features', append=False):
 """Write h5features data in a specified group of the file. :param dict data: A `h5features.Data` instance to be writed on disk. :param str groupname: Optional. The name of the group in which to write the data. :param bool append: Optional. This parameter has no effect if the `groupname` is not an existing group in the file. If set to True, try to append new data in the group. If False (default) erase all data in the group before writing. :raise IOError: if append requested but not possible. """

        if append and groupname in self.h5file:
            # append data to the group, raise if we cannot
            group = self.h5file[groupname]
            if not is_same_version(self.version, group):
                raise IOError(
                    'data is not appendable to the group {}: '
                    'versions are different'.format(group.name))

            if not data.is_appendable_to(group):
                raise IOError(
                    'data is not appendable to the group {}'
                    .format(group.name))
        else:  # overwrite any existing data in group
            group = self._prepare(data, groupname)

        data.write_to(group, append)