<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _parse_fail(name, var_type, value, values):
 """Helper function for raising a value error for bad assignment."""

  raise ValueError(
      'Could not parse hparam \'%s\' of type \'%s\' with value \'%s\' in %s' %
      (name, var_type.__name__, value, values))