code: def to_offset(freq):
      """
      Return DateOffset object from string or tuple representation
      or datetime.timedelta object
  
      Parameters
      ----------
      freq : str, tuple, datetime.timedelta, DateOffset or None
  
      Returns
      -------
      delta : DateOffset
          None if freq is None
  
      Raises
      ------
      ValueError
          If freq is an invalid frequency
  
      See Also
      --------
      pandas.DateOffset
  
      Examples
      --------
      >>> to_offset('5min')
      <5 * Minutes>
  
      >>> to_offset('1D1H')
      <25 * Hours>
  
      >>> to_offset(('W', 2))
      <2 * Weeks: weekday=6>
  
      >>> to_offset((2, 'B'))
      <2 * BusinessDays>
  
      >>> to_offset(datetime.timedelta(days=1))
      <Day>
  
      >>> to_offset(Hour())
      <Hour>
      """
      if freq is None:
          return None
  
      if isinstance(freq, DateOffset):
          return freq
  
      if isinstance(freq, tuple):
          name = freq[0]
          stride = freq[1]
          if isinstance(stride, compat.string_types):
              name, stride = stride, name
          name, _ = libfreqs._base_and_stride(name)
          delta = get_offset(name) * stride
  
      elif isinstance(freq, timedelta):
          delta = None
          freq = Timedelta(freq)
          try:
              for name in freq.components._fields:
                  offset = _name_to_offset_map[name]
                  stride = getattr(freq.components, name)
                  if stride != 0:
                      offset = stride * offset
                      if delta is None:
                          delta = offset
                      else:
                          delta = delta + offset
          except Exception:
              raise ValueError(
                  libfreqs.INVALID_FREQ_ERR_MSG.format(freq)
              )
  
      else:
          delta = None
          stride_sign = None
          try:
              splitted = re.split(libfreqs.opattern, freq)
              if splitted[-1] != "" and not splitted[-1].isspace():
                  # the last element must be blank
                  raise ValueError("last element must be blank")
              for sep, stride, name in zip(
                  splitted[0::4], splitted[1::4], splitted[2::4]
              ):
                  if sep != "" and not sep.isspace():
                      raise ValueError("separator must be spaces")
                  prefix = libfreqs._lite_rule_alias.get(name) or name
                  if stride_sign is None:
                      stride_sign = -1 if stride.startswith("-") else 1
                  if not stride:
                      stride = 1
                  if prefix in Resolution._reso_str_bump_map.keys():
                      stride, name = Resolution.get_stride_from_decimal(
                          float(stride), prefix
                      )
                  stride = int(stride)
                  offset = get_offset(name)
                  offset = offset * int(np.fabs(stride) * stride_sign)
                  if delta is None:
                      delta = offset
                  else:
                      delta = delta + offset
          except Exception:
              raise ValueError(
                  libfreqs.INVALID_FREQ_ERR_MSG.format(freq)
              )
  
      if delta is None:
          raise ValueError(libfreqs.INVALID_FREQ_ERR_MSG.format(freq))
  
      return delta
  
imports: from datetime import timedelta
  import re
  import numpy
  from pytz import AmbiguousTimeError
  from pandas._libs.algos import unique_deltas
  from pandas._libs.tslibs import Timedelta, Timestamp
  from pandas._libs.tslibs.ccalendar import MONTH_ALIASES, int_to_weekday
  from pandas._libs.tslibs.conversion import tz_convert
  from pandas._libs.tslibs.fields import build_field_sarray
  import pandas._libs.tslibs.frequencies
  from pandas._libs.tslibs.offsets import _offset_to_period_map
  import pandas._libs.tslibs.resolution
  from pandas._libs.tslibs.resolution import Resolution
  from pandas._libs.tslibs.timezones import UTC
  import pandas.compat
  from pandas.compat import zip
  from pandas.util._decorators import cache_readonly
  from pandas.core.dtypes.common import is_datetime64_dtype, is_period_arraylike, is_timedelta64_dtype
  from pandas.core.dtypes.generic import ABCSeries
  from pandas.core.algorithms import unique
  from pandas.tseries.offsets import DateOffset, Day, Hour, Micro, Milli, Minute, Nano, Second, prefix_mapping
label_desc: Use image node_id 2 for calling a global function with example usage: to_offset(freq) and returns: delta, None, freq