Python 迭代两个文件，比较行中的匹配字符串，合并匹配行

我有两个文件，里面有一份生物体的清单。第一个文件包含一个指示“家族属”的列表，因此有两列。第二个文件包含“属-种”，也有两列。这两个文件在所有列出的物种的属上是一致的。我想使用每个文件的属合并这两个列表，以便能够将科名称添加到“属物种”中。因此，输出应包含“科-属-种”。由于每个名称之间都有一个空格，所以我使用该空格将其拆分为列。到目前为止，这是我的代码：

with open('FAMILY_GENUS.TXT') as f1, open('GENUS_SPECIES.TXT') as f2:
    for line1 in f1:
        line1 = line1.strip()
        c1 = line1.split(' ')
        print(line1, end=' ')
        for line2 in f2:
            line2 = line2.strip()
            c2 = line2.split(' ')
            if line1[1] == line2[0]:
                print(line2[1], end=' ')
        print()

结果输出仅由两行组成，而不是整个记录。我错过了什么

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还有，我怎样才能把它保存到一个文件中，而不是仅仅在屏幕上打印？

我会先处理这些文件，然后得到它可能包含的属到科和多个物种的映射。然后使用该映射将它们匹配并打印出来

genuses = {}

# Map all genuses to a family
with open('FAMILY_GENUS.TXT') as f1:
    for line in f1:
        family, genus = line.strip().split()
        genuses.setdefault(genus, {})['family'] = family

# Map all species to a genus
with open('GENUS_SPECIES.TXT') as f2:
    for line in f2:
        genus, species = line.strip().split()
        genuses.setdefault(genus, {}).setdefault('species', []).append(species)

# Go through each genus and create a specie string for
# each specie it contains.
species_strings = []
for genus, d in genuses.items():
    family = d.get('family')
    species = d.get('species')
    if family and species:
        for specie in species:
            s = '{0} {1} {2}'.format(family, genus, specie)
            species_strings.append(s)

# Sort the strings to make the output pretty and print them out.
species_strings.sort()
for s in species_strings:
    print s

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这是另一种解决办法

f1 = open('fg','r')
f2 = open('gs','r')
genera= {}
for i in f1.readlines():
    family,genus = i.strip().split(" ")
    genera[genus] = family

for i in f2.readlines():
    genus,species = i.strip().split(" ")
    print(genera[genus], genus,species)