title: ValueError: Attempt to convert a value Tensor
body: <p>I am trying to prepare my.CSV file for deep learning. currently, I am trying to read data from the CSV file. but got an error that cant understand. </p>
  
  <pre><code>import tensorflow as tf
  
  tf.enable_eager_execution()
  
  csv_path = "/Users/dean/Desktop/AI TECNOMATIX EXCEL/cartest1.csv"
  
  def DESAI_map(name, platform, year):
      return {'MachineAvailability': MA, "MachineEntranceLocked": MEnL, "MachineExitLocked": MExL, "MachineMTTR": MTTR, "StatNumIn": SNI, "StatNumOut": SNO}
  
  DESAI_dataset = tf.data.experimental.CsvDataset(
      filenames=csv_path,
      record_defaults=[tf.Variable,tf.string, tf.string, tf.Variable,tf.Variable,tf.Variable([1900], dtype=tf.int32)],
      select_cols=[1, 2, 3,4,5,6],
      field_delim=",",
      header=True)
  
  DESAI_dataset = DESAI_dataset.filter(lambda MA:MA&lt;=99, MEnL, MExL,MTTR,SNI,SNO)
  DESAI_dataset = DESAI_dataset.map(map_func=DESAI_map)
  DESAI_dataset = DESAI_dataset.batch(1)
  
  for data in DESAI_dataset:
      tf.print(data)  # Print : {'Name': [Wii Sports], 'Platform': [Wii], 'Year': [2006]}
      break
  
  
  
  ValueError: Attempt to convert a value (&lt;class 'tensorflow.python.ops.variables.VariableV1'&gt;) with an unsupported type (&lt;class 'tensorflow.python.ops.variables.VariableMetaclass'&gt;) to a Tensor.
  </code></pre>
  
  <h2>Test data</h2>
  
  <pre><code>name,MachineAvailability,MachineEntranceLocked,MachineExitLocked,MachineMTTR,StatNumIn,StatNumOut 
  XX,100,FALSE,FALSE,0,0,0
  XY,100,FALSE,FALSE,0,0,0 
  XX,100,FALSE,FALSE,0,2,2
  XX,100,FALSE,FALSE,0,2,2
  </code></pre>
  
  <h2>Stack trace</h2>
  
  <blockquote>
    <p>ValueError Traceback (most recent call last)  in  13 select_cols=[1, 2, 3,4,5,6], 14 field_delim=",", ---> 15 header=True) 16 17 DESAI_dataset = DESAI_dataset.filter(lambda MA:MA&lt;=99, MEnL, MExL,MTTR,SNI,SNO) </p>
    
    <p>ValueError: Attempt to convert a value () with an unsupported type () to a Tensor.</p>
  </blockquote>
  
  <p>Any help appreciated.</p>
  
  <p>Thanks </p>