project = forms.ChoiceField(label=_("Project"), required=True)

def __init__(self, request, *args, **kwargs):
    super(CreateAction, self).__init__(request,
                                                *args, **kwargs)
    self.fields['project'].choices = (
        self.get_project_list_choices(request))

def get_project_list_choices(self, request):
    project_choices = [('', _("Select a Project"))]
    list_of_projects = self._get_projects(request)
    for obj in list_of_projects:
        project_choices.append((obj.id, obj.name))
    return project_choices

def _get_projects(self, request):
    projects = []
    try:
        projects, has_more = api.keystone.tenant_list(request)
    except Exception:
        msg = _('Project list cannot be retrieved.')
        exceptions.handle(request, msg)
    return projects

I am able to display the list of projects as a dropdown menu