#start
i=0
r=("('/html/body/div[4]/div/div/div[2]/ul/div/li[")
p=("]/div/div[2]/div[1]/div/div/span/a')")
for f in range(7):
i = i+1
browser.find_element_by_xpath("{}{}{}".format(r,i,p)).click()
#end
error i am getting =selenium.common.exceptions.InvalidSelectorException: Message: invalid selector: Unable to locate an element with the xpath expression ('/html/body/div[4]/div/div/div[2]/ul/div/li[1]/div/div[2]/div[1]/div/div/span/a') because of the following error: TypeError: Failed to execute 'evaluate' on 'Document': The result is not a node set, and therefore cannot be converted to the desired type. (Session info: chrome=91.0.4472.77)