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. Your answer need to be wrapped in double quotes. Make sure to highlight at least 2 sections in your answer with markdown, i.e. use *highlighted section*. All letters in your response must be lower case letters. The words health cannot be in the response. Mention the word "relationships" for less than 2 times. Keep your entire response at least 13 words or less.. Please reply in details, and include exactly 3 paragraphs. Separate the paragraphs with ***.
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Please reply in details, and include exactly 3 paragraphs. Separate the paragraphs with *** Keep your entire response at least 13 words or less. Mention the word "relationships" for less than 2 times The words health cannot be in the response All letters in your response must be lower case letters Make sure to highlight at least 2 sections in your answer with markdown, i.e. use *highlighted section* Your answer need to be wrapped in double quotes