Write a Python program that takes a list of numbers as input from the user, calculates the sum of all even numbers in the list, and returns the result. The program should check if the input is valid (i.e., if it's a list of numbers), and if it's not, it should return an error message. The program should also handle exceptions gracefully and return a user-friendly error message in case of any exceptions.
startend:end_checker punctuation:no_comma keywords:existence length_constraints:number_words length_constraints:number_paragraphs detectable_format:number_highlighted_sections keywords:frequency
your love, and thanks.
financial
less than
less than
digital
Finish the response with this exact phrase: your love, and thanks.  Refrain from using commas in your response Make sure to include the words financial Limit the number of words you use (less than 66 words) make sure there are exactly 4 sections. Separated the sections by the markdown divider: *** You must highlight at least 3 words or phrases in your response, like *highlighted phrase* Make sure to use the word digital less than 3 times