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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 _validate_logical_id(cls, logical_id):
 """Validates that the provided logical id is an alphanumeric string. :param str logical_id: the logical id to validate :returns: True if the logical id is valid :rtype: bool :raises TypeError: if the logical id is invalid """

        pattern = re.compile(r'^[A-Za-z0-9]+$')
        if logical_id is not None and pattern.match(logical_id):
            return True
        raise InvalidResourceException(logical_id, "Logical ids must be alphanumeric.")