input: Write a function to format a given piece of text (input) with different options for font-style, size, and color. The function should return the formatted text as a string. If no options are provided, the function should use default values for font-style (Times New Roman), size (14px), and color (#000000).
  
  def format_text(text, font="Times New Roman", size='14px', color='#000000'):
    return "<span style='font-family: {}; font-size: {}; color: {};'>{}</span>".format(font, size, color, text)
  
  assert format_text('Lorem ipsum dolor sit amet, consectetur adipiscing elit.') == "<span style='font-family: Times New Roman; font-size: 14px; color: #000000;'>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</span>"
  assert format_text('Aliquam non velit sit amet arcu placerat vulputate a ut nibh.', font='Arial', size='16px', color='#FF0000') == "<span style='font-family: Arial; font-size: 16px; color: #FF0000;'>Aliquam non velit sit amet arcu placerat vulputate a ut nibh.</span>"
  assert format_text('Integer ut lectus vel nisi consequat bibendum ac a erat.', size='18px') == "<span style='font-family: Times New Roman; font-size: 18px; color: #000000;'>Integer ut lectus vel nisi consequat bibendum ac a erat.</span>"
  assert format_text('Aliquam non velit sit amet arcu placerat vulputate a ut nibh.', color='#00FF00') == "<span style='font-family: Times New Roman; font-size: 14px; color: #00FF00;'>Aliquam non velit sit amet arcu placerat vulputate a ut nibh.</span>"
  assert format_text('', font='Courier New') == "<span style='font-family: Courier New; font-size: 14px; color: #000000;'></span>"
output: def format_text(text, font="Times New Roman", size='14px', color='#000000'):
    return "<span style='font-family: {}; font-size: {}; color: {};'>{}</span>".format(font, size, color, text)