I am trying snakemake for my mRNA-seq pipeline and I got stuck in a simple thing.

from os.path import join


RSEM_INDEX = "/app/ref/ensembl/human/idx/GRCh37"
SAMPLES, = glob_wildcards("Align/{sample}/Aligned.toTranscriptome.out.bam")

print("---Sample Names---")

for i in SAMPLES:
    print(i)

rule all:
    input:
        expand("Expression/{sample}/rsem.genes.results", sample=SAMPLES)


rule expression:
    input:
        bam = join("Align", "{wildcards.sample}}", "Aligned.toTranscriptome.out.bam")
    params:
        rsem_index = RSEM_INDEX
    output:
        join("Expression", "{wildcards.sample}", "rsem.genes.results")
    threads:
        8
    shell:
        """
        rsem-calculate-expression --estimate-rspd --bam --no-bam-output -p {threads} --paired-end Align/{sample}/Aligned.toTranscriptome.out.bam {params.rsem_index} Expression/{wildcards.sample}/rsem.genes.results >& Expression/{wildcards.sample}/rsem.log
        """

Here is an error I got

    MissingInputException in line 12 of /app/src/mRNAseq/TBD170049_20170320_RNAseq/quantify.snakemake:
Missing input files for rule all:
Expression/013_clamp_0m_buffy/rsem.genes.results
Expression/12_27_11_clamp_buffy_200/rsem.genes.results
Expression/010_200_buffy/rsem.genes.results
Expression/010_0_buffy/rsem.genes.results
Expression/12_27_11_clamp-p_buffy_0/rsem.genes.results
Expression/013_clamp_200m_buffy/rsem.genes.results
Expression/11_15_006_0m_buffy/rsem.genes.results
Expression/11_15_006_200m_buffy/rsem.genes.results

I thought rule all input for your final files you want to make, but it's looking for the final files that are not made yet. I would like to get some help. would you help me please? Thank you in advance!

My file trees.

drwxrwxr-x. 10 corea corea  4096 Sep 26 20:54 Align
-rw-rw-r--.  1 corea corea  1295 Sep 27 10:19 align.snakemake
-rw-rw-r--.  1 corea corea  1823 Sep 27 09:38 align.snakemake.test
-rw-rw-r--.  1 corea corea 31055 Sep 26 08:55 out
-rw-rw-r--.  1 corea corea   869 Sep 27 12:34 quantify.snakemake
drwxrwxr-x.  2 corea corea  4096 Sep 22 20:50 Rawdata
(mRNAseq) [corea@Biocore76 TBD170049_20170320_RNAseq]$ tree Align/
Align/
├── 010_0_buffy
│   ├── Aligned.out.bam
│   ├── Aligned.toTranscriptome.out.bam
│   ├── Log.final.out
│   ├── Log.out
│   ├── Log.progress.out
│   ├── SJ.out.tab
│   ├── _STARgenome
│   │   ├── sjdbInfo.txt
│   │   └── sjdbList.out.tab
│   └── _STARpass1
│       ├── Log.final.out
│       └── SJ.out.tab
├── 010_200_buffy
│   ├── Aligned.out.bam
│   ├── Aligned.toTranscriptome.out.bam
│   ├── Log.final.out
│   ├── Log.out
│   ├── Log.progress.out
│   ├── SJ.out.tab
│   ├── _STARgenome
│   │   ├── sjdbInfo.txt
│   │   └── sjdbList.out.tab
│   └── _STARpass1
│       ├── Log.final.out
│       └── SJ.out.tab
├── 013_clamp_0m_buffy