def validate_data_provider(value)
      if value.is_a?(String)
        unless value =~ /^[a-zA-Z][a-zA-Z0-9_]*$/
          if value =~ /^[a-zA-Z]/
            raise ArgumentError, _("field 'data_provider' contains non-alphanumeric characters")
          else
            raise ArgumentError, _("field 'data_provider' must begin with a letter")
          end
        end
      else
        raise ArgumentError, _("field 'data_provider' must be a string")
      end
    end
def validate_data_provider(value)
      if value.is_a?(String)
        unless value =~ /^[a-zA-Z][a-zA-Z0-9_]*$/
          if value =~ /^[a-zA-Z]/
            raise ArgumentError, _("field 'data_provider' contains non-alphanumeric characters")
          else
            raise ArgumentError, _("field 'data_provider' must begin with a letter")
          end
        end
      else
        raise ArgumentError, _("field 'data_provider' must be a string")
      end
    end
Validates that the given _value_ is a symbolic name that starts with a letter
 and then contains only letters, digits, or underscore. Will raise an ArgumentError
 if that's not the case.

 @param value [Object] The value to be tested