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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 find_schema(schema_dir, obj_type):
 """Search the `schema_dir` directory for a schema called `obj_type`.json. Return the file path of the first match it finds. """

    schema_filename = obj_type + '.json'

    for root, dirnames, filenames in os.walk(schema_dir):
        if schema_filename in filenames:
            return os.path.join(root, schema_filename)