def _build_selector(selectors, separator):
    """
    Build a selector defined by the selector and separator
    :param selectors: a list of strings that are selector
    :param separator: the char that separates the different selectors
    :return: the resulting selector
    """
    selector = ""
    for i, sel in enumerate(selectors):
        if i != 0:
            selector += separator
        selector += "$" + sel.replace(" ", "%20")
    return selector