下拉框结构如下，我需要选择的是new：

html为：

<select id="condition_type" name="condition_type" class="notification-required notification-required-unknown">

	<option value="">

			- Select -</option>

	<option value="new, new">

			New</option>

	<option value="used, like_new">

			Used - Like New</option>

	<option value="used, very_good">

			Used - Very Good</option>

	<option value="used, good">

			Used - Good</option>

	<option value="used, acceptable">

			Used - Acceptable</option>

	<option value="refurbished, refurbished">

			Refurbished</option>

	</select>

代码：

from selenium.webdriver.support.select import Select

# 定位到下拉框，选择new

sel = browser.find_element_by_xpath("//select[@id='condition_type']")

Select(sel).select_by_value('new, new')