'Populate or unpopulate the toolshed and changeset_revision attributes of a
<repository> tag that defines a complex repository dependency.'

def handle_complex_dependency_elem(self, parent_elem, elem_index, elem):

    (altered, new_elem, error_message) = self.handle_elem(elem)
    if error_message:
        error_message += ('        The    %s    file    contains    an    invalid    <repository>    tag.' % TOOL_DEPENDENCY_DEFINITION_FILENAME)
    return (altered, new_elem, error_message)
