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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 get_attribute_id(self, attribute_key):
 """ Get attribute ID for the provided attribute key. Args: attribute_key: Attribute key for which attribute is to be fetched. Returns: Attribute ID corresponding to the provided attribute key. """


    attribute = self.attribute_key_map.get(attribute_key)
    has_reserved_prefix = attribute_key.startswith(RESERVED_ATTRIBUTE_PREFIX)

    if attribute:
      if has_reserved_prefix:
        self.logger.warning(('Attribute %s unexpectedly has reserved prefix %s; using attribute ID '
                             'instead of reserved attribute name.' % (attribute_key, RESERVED_ATTRIBUTE_PREFIX)))

      return attribute.id

    if has_reserved_prefix:
      return attribute_key

    self.logger.error('Attribute "%s" is not in datafile.' % attribute_key)
    self.error_handler.handle_error(exceptions.InvalidAttributeException(enums.Errors.INVALID_ATTRIBUTE_ERROR))
    return None