<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_url_from_model_core(request, obj):
 """ Returns object URL from model core. """

    from is_core.site import get_model_core
    model_core = get_model_core(obj.__class__)

    if model_core and hasattr(model_core, 'ui_patterns'):
        edit_pattern = model_core.ui_patterns.get('detail')
        return (
            edit_pattern.get_url_string(request, obj=obj)
            if edit_pattern and edit_pattern.has_permission('get', request, obj=obj) else None
        )
    else:
        return None