code: def set_default_printstyle(style):
      """
      Set the default format for the string representation of polynomials.
  
      Values for ``style`` must be valid inputs to ``__format__``, i.e. 'ascii'
      or 'unicode'.
  
      Parameters
      ----------
      style : str
          Format string for default printing style. Must be either 'ascii' or
          'unicode'.
  
      Notes
      -----
      The default format depends on the platform: 'unicode' is used on
      Unix-based systems and 'ascii' on Windows. This determination is based on
      default font support for the unicode superscript and subscript ranges.
  
      Examples
      --------
      >>> p = np.polynomial.Polynomial([1, 2, 3])
      >>> c = np.polynomial.Chebyshev([1, 2, 3])
      >>> np.polynomial.set_default_printstyle('unicode')
      >>> print(p)
      1.0 + 2.0·x + 3.0·x²
      >>> print(c)
      1.0 + 2.0·T₁(x) + 3.0·T₂(x)
      >>> np.polynomial.set_default_printstyle('ascii')
      >>> print(p)
      1.0 + 2.0 x + 3.0 x**2
      >>> print(c)
      1.0 + 2.0 T_1(x) + 3.0 T_2(x)
      >>> # Formatting supersedes all class/package-level defaults
      >>> print(f"{p:unicode}")
      1.0 + 2.0·x + 3.0·x²
      """
      if style not in ("unicode", "ascii"):
          raise ValueError(
              f"Unsupported format string '{style}'. Valid options are 'ascii' "
              f"and 'unicode'"
          )
      _use_unicode = True
      if style == "ascii":
          _use_unicode = False
      from ._polybase import ABCPolyBase
  
      ABCPolyBase._use_unicode = _use_unicode
  
file_path: numpy/numpy/polynomial/__init__.py
imports: from .polynomial import Polynomial
  from .chebyshev import Chebyshev
  from .legendre import Legendre
  from .hermite import Hermite
  from .hermite_e import HermiteE
  from .laguerre import Laguerre
  from numpy._pytesttester import PytestTester
label_desc: Use image node_id 1 for calling a global function with example usage: set_default_printstyle(style) without return types