Pytest Selenium elem.send_keys() causing TypeError: object of type 'NoneType' has no len() - selenium

Question

I am trying to send data to a login textbox but when I use 'send_keys' I get an error..
def wait_for_element(selenium, selenium_locator, search_pattern, wait_seconds=10):
elem = None
wait = WebDriverWait(selenium, wait_seconds)
try:
if (selenium_locator.upper() == 'ID'):
elem = wait.until(
EC.visibility_of_element_located((By.ID, search_pattern))
)
except TimeoutException:
pass
return elem
userid=os.environ.get('userid')
wait_for_element(selenium, "ID", 'username')
assert elem is not None
elem.click()
time.sleep(3)
elem.send_keys(userid)
tests\util.py:123: in HTML5_login
elem.send_keys(userid)
..\selenium\webdriver\remote\webelement.py:478: in send_keys
{'text': "".join(keys_to_typing(value)),
value = (None,)
def keys_to_typing(value):
"""Processes the values that will be typed in the element."""
typing = []
for val in value:
if isinstance(val, Keys):
typing.append(val)
elif isinstance(val, int):
val = str(val)
for i in range(len(val)):
typing.append(val[i])
else:
for i in range(len(val)):
for i in range(len(val)):
E TypeError: object of type 'NoneType' has no len()
I have no clue why it is saying the element is of "NoneType" when I have it pass an assertion as well as click the element. I can even see it clicking the element when I run the test!

Answer 1

This error message...
elem.send_keys(userid) ..\selenium\webdriver\remote\webelement.py:478: in send_keys {'text': "".join(keys_to_typing(value)), value = (None,)
TypeError: object of type 'NoneType' has no len()
...implies that send_keys() method encountered an error when sending the contents of the variable userid.
Though you have tried to use the variable userid, I don't see the variable userid being declared anywhere within your code block. Hence you see the error:
TypeError: object of type 'NoneType' has no len()
Solution
Initialize the userid variable as:
userid = "Austin"
Now, execute your test.