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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 encode_value(value):
 """Converts a native Python value into a Firestore protobuf ``Value``. Args: value (Union[NoneType, bool, int, float, datetime.datetime, \ str, bytes, dict, ~google.cloud.Firestore.GeoPoint]):
 A native Python value to convert to a protobuf field. Returns: ~google.cloud.firestore_v1beta1.types.Value: A value encoded as a Firestore protobuf. Raises: TypeError: If the ``value`` is not one of the accepted types. """

    if value is None:
        return document_pb2.Value(null_value=struct_pb2.NULL_VALUE)

    # Must come before six.integer_types since ``bool`` is an integer subtype.
    if isinstance(value, bool):
        return document_pb2.Value(boolean_value=value)

    if isinstance(value, six.integer_types):
        return document_pb2.Value(integer_value=value)

    if isinstance(value, float):
        return document_pb2.Value(double_value=value)

    if isinstance(value, DatetimeWithNanoseconds):
        return document_pb2.Value(timestamp_value=value.timestamp_pb())

    if isinstance(value, datetime.datetime):
        return document_pb2.Value(timestamp_value=_datetime_to_pb_timestamp(value))

    if isinstance(value, six.text_type):
        return document_pb2.Value(string_value=value)

    if isinstance(value, six.binary_type):
        return document_pb2.Value(bytes_value=value)

    # NOTE: We avoid doing an isinstance() check for a Document
    #       here to avoid import cycles.
    document_path = getattr(value, "_document_path", None)
    if document_path is not None:
        return document_pb2.Value(reference_value=document_path)

    if isinstance(value, GeoPoint):
        return document_pb2.Value(geo_point_value=value.to_protobuf())

    if isinstance(value, list):
        value_list = [encode_value(element) for element in value]
        value_pb = document_pb2.ArrayValue(values=value_list)
        return document_pb2.Value(array_value=value_pb)

    if isinstance(value, dict):
        value_dict = encode_dict(value)
        value_pb = document_pb2.MapValue(fields=value_dict)
        return document_pb2.Value(map_value=value_pb)

    raise TypeError(
        "Cannot convert to a Firestore Value", value, "Invalid type", type(value)
    )