def _validate_variable_names(variables):
 variable_names = [v.name for v in variables]
 name_counts = Counter(variable_names)
 if (None in name_counts):
  none_names = [v for v in variables if (v.name is None)]
  raise ValueError('Variables must have names: {}'.format(none_names))
 if any(((v > 1) for v in name_counts.values())):
  raise ValueError('Variables should have unique names. Duplicates: {}'.format(', '.join((k for (k, v) in name_counts.items() if (v > 1)))))

def _validate_variable_names ( variables ) : variable_names = [ v . name for v in variables ] name_counts = Counter ( variable_names ) if ( None in name_counts ) : none_names = [ v for v in variables if ( v . name is None ) ] raise ValueError ( 'Variables must have names: {}' . format ( none_names ) ) if any ( ( ( v > 1 ) for v in name_counts . values ( ) ) ) : raise ValueError ( 'Variables should have unique names. Duplicates: {}' . format ( ', ' . join ( ( k for ( k , v ) in name_counts . items ( ) if ( v > 1 ) ) ) ) )
check for missing and duplicate variable names .