What is entry point of BigQuery Cloud Function?

I successfully updated a BigQuery Table Using an External API and a Cloud Function. My entry point of the code below is hello_pubsub, however, I do not know what those 2 parameters are. I didn't provide event and context to the function, how can it still run my code without errors? Though I know the code in the function provide all the information to do the loading job.

import pandas as pd
import requests
from datetime import datetime
from google.cloud import bigquery

def hello_pubsub(event, context):

    PROJECT = "test-391108"

    client = bigquery.Client(project=PROJECT)
    
    table_id = "test-391108.TEAM.MEMBER"

    API_ENDPOINT ='https://fantasy.premierleague.com/api/bootstrap-static/'

    response = requests.get(API_ENDPOINT, timeout=5)
    response_json = response.json()
    df = pd.DataFrame(response_json['teams'])
    df = df.iloc[:,:6]

    job_config = bigquery.LoadJobConfig(write_disposition="WRITE_TRUNCATE")
    job = client.load_table_from_dataframe(df, table_id, job_config=job_config)

Is there also another way I can schedule my code without using function and load data into Bigquery table by using an External API?

Posting @Mike Karp's comment as an answer for better visibility for the community.

>The two variables event and context are what is expected when you set up a PubSub trigger

For reference a definition of the variables are cited here:
https://cloud.google.com/functions/docs/writing/write-event-driven-functions#background-functions