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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 get_maven_id(jar_path):
 """Extract Maven coordinates from a given JAR file, if possible. JARs build by Maven (most popular Java build system) contain 'pom.properties' file. We can extract Maven coordinates from there. """

        props = {}
        try:
            with zipfile.ZipFile(jar_path) as f:
                r = re.compile("META-INF/maven/[^/]+/[^/]+/pom.properties$")
                result = [x for x in f.namelist() if r.match(x)]
                if len(result) != 1:
                    return None
                with f.open(result[0]) as props_f:
                    for line in props_f.readlines():
                        line = line.strip()
                        if not line.startswith(b"#"):
                            try:
                                (key, value) = line.split(b"=")
                                key = key.decode('utf8').strip()
                                value = value.decode('utf8').strip()
                                props[key] = value
                            except ValueError:
                                return None
        except IOError:
            pass
        return props