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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 get_output_base_path( self, output_directory, output_prefix, feature_type, overwrite):
 """Get a full base name path to save the shapefile. :param output_directory: The directory where to put results. :type output_directory: str :param output_prefix: The prefix to add for the shapefile. :type output_prefix: str :param feature_type: What kind of features should be downloaded. Currently 'buildings', 'building-points' or 'roads' are supported. :type feature_type: str :param overwrite: Boolean to know if we can overwrite existing files. :type overwrite: bool :return: The base path. :rtype: str """

        path = os.path.join(
            output_directory, '%s%s' % (output_prefix, feature_type))

        if overwrite:

            # If a shapefile exists, we must remove it (only the .shp)
            shp = '%s.shp' % path
            if os.path.isfile(shp):
                os.remove(shp)

        else:
            separator = '-'
            suffix = self.get_unique_file_path_suffix(
                '%s.shp' % path, separator)

            if suffix:
                path = os.path.join(output_directory, '%s%s%s%s' % (
                    output_prefix, feature_type, separator, suffix))

        return path