input: Write a function to format a given piece of text with different options for font-style, size, and color. The function should return the formatted text as an HTML span element. If no formatting options are provided, the default font should be "Times New Roman", the default size should be "14px", and the default color should be "#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('Integer ut lectus vel nisi consequat bibendum ac a erat.', font="Arial", size="16px", color="#1A83FF")=="<span style='font-family: Arial; font-size: 16px; color: #1A83FF;'>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.')=="<span style='font-family: Times New Roman; font-size: 14px; color: #000000;'>Aliquam non velit sit amet arcu placerat vulputate a ut nibh.</span>"
  assert format_text('')=="<span style='font-family: Times New Roman; font-size: 14px; color: #000000;'></span>"
  assert format_text('This is some text in a different font.', font="Verdana", size="12px")=="<span style='font-family: Verdana; font-size: 12px; color: #000000;'>This is some text in a different font.</span>"
  assert format_text('The default color is black.', color="#FFFFFF", size="20px")=="<span style='font-family: Times New Roman; font-size: 20px; color: #FFFFFF;'>The default color is black.</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)