Updates from db

        return obj

    def copy_images(self, newpath):

    def copy_images(self, newdir):

        """

        Copy images from a given directory into a new directory and

        update the 'path' column in the Images table.

        Parameters

        ----------

        newdir : str

                 The full output PATH where the images are to be copied to.

        """

        if not os.path.exists(newpath):

            os.makedirs(newpath)

        if not os.path.exists(newdir):

            os.makedirs(newdir)

        session = Session()

        images = session.query(Images.path).all()

        images = session.query(Images).all()

        oldnew = []

        for obj in images:

            oldpath = obj.path

            filename = os.path.basename(oldpath)

            newpath = os.path.join(newpath, filename)

            obj.path = newpath

            oldnew.append((oldpath, newpath))

            obj.path = os.path.join(newdir, filename)

            oldnew.append((oldpath, obj.path))

        session.commit()

        session.close()

        # Copy the files

        [shutil(old, new) for old, new in oldnew]]

        [copyfile(old, new) for old, new in oldnew]

    @classmethod

    def from_remote_database(cls, config, path,  query_string='SELECT * FROM public.images'):

        similar to the `from_database` method. The main difference is that this

        method assumes that the image and sensor rows are prepopulated in an external db

        and simply copies those entires into the currently speficied project.

        Currently, this method does NOT check for duplicate serial numbers during the 

        bulk add. Therefore multiple runs of this method on the same database will fail.

        Parameters

        ----------

        config : dict

                 In the form: {'username':'somename',

                               'password':'somepassword',

                               'host':'somehost',

                               'pgbouncer_port':6543,

                               'name':'somename'}

        path : str

               The PATH to which images in the database specified in the config

               will be copied to. This method duplicates the data and copies it

               to a user defined PATH to avoid issues with updating image ephemeris

               across projects.

        query_string : str

                       An optional string to select a subset of the images in the 

                       database specified in the config. 

        Returns

        -------

        obj : obj

              A network candidate graph.

        Example

        -------

        >>> config = {'username':'jay',

          'password':'abcde',

          'host':'autocnet.wr.usgs.gov',

          'pgbouncer_port':5432,

          'name':'ctx'}

        >>> geom = 'LINESTRING(145 10, 145 11, 146 11, 146 10, 145 10)'

        >>> srid = 949900

        >>> outpath = '/scratch/jlaura/fromdb'

        >>> query = f"SELECT * FROM Images WHERE ST_INTERSECTS(footprint_latlon, ST_Polygon(ST_GeomFromText('{geom}'), {srid})) = TRUE"

        >>> ncg = NetworkCandidateGraph.from_remote_database(config, outpath, query_string=query)

        """

        sourceSession, _ = new_connection(config)

        sourcesession = sourceSession()

        return obj

    @classmethod

    def from_database(cls, path, query_string='SELECT * FROM public.images'):

    def from_database(cls, query_string='SELECT * FROM public.images'):

        """

        This is a constructor that takes the results from an arbitrary query string,

        uses those as a subquery into a standard polygon overlap query and