code: def lshift(x1, x2, out=None, where=None, **kwargs):
      """
      Shift the bits of an integer to the left.
  
      Bits are shifted to the left by appending `x2` 0s at the right of `x1`.
      Since the internal representation of numbers is in binary format, this
      operation is equivalent to multiplying `x1` by ``2**x2``.
  
      Parameters
      ----------
      x1 : array_like of integer type
          Input values.
      x2 : array_like of integer type
          Number of zeros to append to `x1`. Has to be non-negative.
      out : Tensor, None, or tuple of Tensor and None, optional
          A location into which the result is stored. If provided, it must have
          a shape that the inputs broadcast to. If not provided or `None`,
          a freshly-allocated tensor is returned. A tuple (possible only as a
          keyword argument) must have length equal to the number of outputs.
      where : array_like, optional
          Values of True indicate to calculate the ufunc at that position, values
          of False indicate to leave the value in the output alone.
      **kwargs
  
      Returns
      -------
      out : tensor of integer type
          Return `x1` with bits shifted `x2` times to the left.
  
      See Also
      --------
      right_shift : Shift the bits of an integer to the right.
  
      Examples
      --------
      >>> import mars.tensor as mt
  
      >>> mt.left_shift(5, 2).execute()
      20
  
      >>> mt.left_shift(5, [1,2,3]).execute()
      array([10, 20, 40])
      """
      op = TensorLshift(**kwargs)
      return op(x1, x2, out=out, where=where)
  
file_path: mars/mars/tensor/arithmetic/lshift.py
imports: import numpy
  from ...None import opcodes
  from ..utils import infer_dtype
  from .core import TensorBinOp
  from .utils import arithmetic_operand
label_desc: Use image node_id 1 for calling a global function with example usage: lshift(x1, x2, out, where) and returns: op