Python class to overlay metadata in CONTENTdm via Catcher (edit only). Catcher docs at: http://contentdm.org/help6/addons/catcher.asp Sample script using this class at: https://gist.github.com/saverkamp/9198310

catcher.py

from suds.client import Client

class Catcher(object):
    """A CONTENTdm Catcher session."""
    def __init__(self, url=url, user=user, password=password, license=license):
        self.transactions = []
        self.client = Client('https://worldcat.org/webservices/contentdm/catcher/6.0/CatcherService.wsdl')
        self.url = url
        self.user = user
        self.password = password
        self.license = license

    def processCONTENTdm(self, action, user, password, license, alias, metadata):
        # function to connect to CatcherServices and process metadata updates
        transaction = self.client.service.processCONTENTdm(action, url, user, password, license, alias, metadata)
        self.transactions.append(transaction)

    def edit(self, alias, recordid, field, value):
        #function to edit metadata--call packageMetadata and processCONTENTdm
        metadata = self.packageMetadata('edit', recordid, field, value)
        self.processCONTENTdm('edit', self.user, self.password, self.license, alias, metadata)

    def packageMetadata(self, action, recordid, field, value):
        #function to package metadata in metadata wrapper
        action = action
        if action == 'edit':
            metadata = self.client.factory.create('metadataWrapper')
            metadata.metadataList = self.client.factory.create('metadataWrapper.metadataList')
            metadata1 = self.client.factory.create('metadata')
            metadata1.field = 'dmrecord'
            metadata1.value = recordid
            metadata2 = self.client.factory.create('metadata')
            metadata2.field = field
            metadata2.value = value
            metadata.metadataList.metadata = [metadata1, metadata2]
        return metadata