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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 pg_backup(self, pg_dump_exe='pg_dump', exclude_schema=None):
 """Call the pg_dump command to create a db backup Parameters pg_dump_exe: str the pg_dump command path exclude_schema: str[] list of schemas to be skipped """


        command = [
            pg_dump_exe, '-Fc', '-f', self.file,
            'service={}'.format(self.pg_service)
            ]
        if exclude_schema:
            command.append(' '.join("--exclude-schema={}".format(schema) for schema in exclude_schema))

        subprocess.check_output(command, stderr=subprocess.STDOUT)