def construct_xml_global_options(url, username):
    """This function constructs the global options portion of the XML file.

    Inputs:
        - url: URL of the Collaborator server [string]
        - username: Username for the Collaborator user [string]

    Outputs:
        - global_options_string: A string containing the global options [string]
    """

    # Create the global options string
    global_options_string = ('    <global-options>\n' +
                             '        <no-browser/>\n' +
                             '        <scm>none</scm>\n' +
                             '        <url>{}</url>\n'.format(url) +
                             '        <user>{}</user>\n'.format(username) +
                             '    </global-options>\n')

    return global_options_string