import jax.numpy as jnp
from jax import eval_shape
from jax.core import ShapedArray

# Define ShapedArray inputs with specified shapes and data types.
a = ShapedArray((2, 3), jnp.float32)
b = ShapedArray((4, 3), jnp.float32)

# Wrap the inputs in a list and specify axis for concatenation.
abstract_args = ([a, b],)  # Single positional argument: sequence of arrays
kwargs = {"axis": 0}

# Use eval_shape to compute the shape and dtype of the result without actual computation.
result = eval_shape(jnp.concatenate, *abstract_args, **kwargs)

# Print the evaluated shape and dtype of the result.
print(result.shape)  # (6, 3)
print(result.dtype)  # float32
