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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def configs_in(src_dir):
 """Enumerate all configs in src_dir"""

    for filename in files_in_dir(src_dir, 'json'):
        with open(os.path.join(src_dir, filename), 'rb') as in_f:
            yield json.load(in_f)