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. You are not allowed to use any commas in your response. answer exactly 4 paragraphs. Use 2 new lines to separate paragraphs. Start the first paragraph with the word "Stuart". Please wrap your entire reply with double quotation marks. The number of sentences in your response should be less than 3. reply should include the word "Stuart" less than 2 times. Make sure the answer contains exactly 2 bullet points in markdown format. Your response must contain 3 sections, mark the beginning of each section with SECTION X.
length_constraints:nth_paragraph_first_word length_constraints:number_sentences punctuation:no_comma detectable_format:multiple_sections keywords:frequency detectable_format:number_bullet_lists startend:quotation
answer exactly 4 paragraphs. Use 2 new lines to separate paragraphs. Start the first paragraph with the word "Stuart" The number of sentences in your response should be less than 3 You are not allowed to use any commas in your response Your response must contain 3 sections, mark the beginning of each section with SECTION X reply should include the word "Stuart" less than 2 times Make sure the answer contains exactly 2 bullet points in markdown format Please wrap your entire reply with double quotation marks