sub get_abandonned($) {                                # Subroutine definition.
  my $dnis = shift;                                    # $dnis will hold
                                                       # the parameter.

  my $total = 0;                                       # $total holds 0.

  for my $key(keys %all_calls) {                       # There is a hash named
                                                       # %all_calls.  Iterate
                                                       # over the keys of the
                                                       # hash and assign each
                                                       # key to $key on its
                                                       # respective iteration.

    next if ($key =~ /duplicate/);                     # Proceed to next
                                                       # iteration if the
                                                       # current key contains
                                                       # the text 'duplicate'.

    if(                                                # If all of the
                                                       # following are true:
         $all_calls{$key}->[DNIS] eq $dnis
      && $all_calls{$key}->[SPEECH] == 0
      && $all_calls{$key}->[TRANSFER] eq "hungup"
    ) {                                                # then do the following:

      my $time_length                                  # Give a value to
                                                       # time_length,
        = &get_call_length($all_calls{$key}->[TIME]);  # from this function
                                                       # call.

      if($time_length <= -29) {                        # Now if this is true...
        $total++;                                      # increment $total.
      }
    }
  }                                                    # Move on to next key.
  return $total;                                       # return the $total.
}