Write a method named isValidEmail that takes a string as inputparameter, and returns true if that string represents a valid emailaddress, or false otherwise. An email address is considered validif it follows this format “user123@domain.ext”, where:
user123 represents a sequence of word characters (i.e.,letters, digits, or underscore) whose length is between 1 and 10(inclusive), but the first character must be a letter
domain represents a sequence of alphanumeric characters (i.e.,letters or digits) whose length is between 1 and 12 (inclusive),but the first character must be a letter
Exactly one character “@” separates the user name from thedomain name
ext is
OR
OR