input: Write a python function to fetch JSON data from a given URL and convert it into a pandas DataFrame.
  assert not fetch_and_convert_to_df('https://jsonplaceholder.typicode.com/posts').empty
  assert isinstance(fetch_and_convert_to_df('https://jsonplaceholder.typicode.com/users'), pd.DataFrame)
  assert 'id' in fetch_and_convert_to_df('https://jsonplaceholder.typicode.com/comments').columns
output: import pandas as pd
  import requests
  
  def fetch_and_convert_to_df(url):
      response = requests.get(url)
      response.raise_for_status()  # Raise an error for bad status codes
      data = response.json()
      df = pd.DataFrame(data)
      return df