package ThisIsMyPackge;

package Foo;

package A
our @ISA = qw{Foo};
sub validate {
  do something;
}

package B
our @ISA = qw{Foo};
sub validate {
  do something;
}

package C
our @ISA = qw{Foo};
sub validate {
  do something;
}

package Bar;

package D
our @ISA = qw{Bar}
sub apply {
  do something;
}

package E
our @ISA = qw{Bar}
sub apply {
  do something;
}

package F
our @ISA = qw{Bar}
sub apply {
  do something;
}