code: def parse_x(self, x):
      if type(x) == str:
          return {x: None}, True
      if type(x) == list:
          return {xi: None for xi in x}, True
      if type(x) == dict:
          return x, False
      raise Exception("x format not recognized: {}".format(type(x)))
  
file_path: dowhy/dowhy/api/causal_data_frame.py
imports: import networkx
  import pandas
  import dowhy.do_samplers
  from dowhy import EstimandType
  from dowhy.graph import build_graph
  from dowhy.utils.api import parse_state
label_desc: Use image node_id 5 for calling the CausalAccessor obj's underlying member method code with example usage: obj.parse_x(x) and returns: dict,  True, unknown,  True, x,  False