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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_email_address(string):
 """ Check whether the specified string corresponds to an email address. @param string: a string that is expected to be an email address. @return: ``True`` if the string corresponds to an email address, ``False`` otherwise. """

    return string and isinstance(string, base_string) \
        and REGEX_PATTERN_EMAIL_ADDRESS.match(string.strip().lower())