code: def sample_params(self, tree):
      sample_type = None
      sample_freq = None
      for child in tree.children:
          if child.data == "sample_clause":
              sample_freq = self.visit(child)
          elif child.data == "sample_clause_with_type":
              sample_type, sample_freq = self.visit(child)
      return sample_type, sample_freq
  
imports: import numpy
  from lark import Tree
  from evadb.catalog.catalog_type import ColumnType
  from evadb.expression.abstract_expression import ExpressionType
  from evadb.expression.comparison_expression import ComparisonExpression
  from evadb.expression.constant_value_expression import ConstantValueExpression
  from evadb.expression.logical_expression import LogicalExpression
  from evadb.utils.generic_utils import string_comparison_case_insensitive
label_desc: Use image node_id 11 for calling the Expressions obj's underlying member method code with example usage: obj.sample_params(tree) and returns: sample_type,  sample_freq